Update contributor code of conduct (#191)

.github/CODE_OF_CONDUCT.md

@@ -2,66 +2,101 @@
 
 ## Our Pledge
 
-As contributors and maintainers of this project, and in order to keep Yii community open and welcoming, we ask to respect all community members.
+As contributors and maintainers of this project, and in order to keep Yii community open and welcoming, we ask to
+respect all community members.
 
 ## Our Standards
 
-Examples of behavior that contributes to creating a positive environment include:
+Examples of behavior that contributes to a positive environment for our community include:
 
-* Using welcoming and inclusive language
-* Being respectful of differing viewpoints and experiences
-* Gracefully accepting constructive criticism
-* Focusing on what is best for the community
-* Showing empathy towards other community members
+* Demonstrating empathy and kindness toward other people
+* Being respectful of differing opinions, viewpoints, and experiences
+* Giving and gracefully accepting constructive feedback
+* Accepting responsibility and apologizing to those affected by our mistakes, and learning from the experience
+* Focusing on what is best not just for us as individuals, but for the overall community
 
 Examples of unacceptable behavior by participants include:
 
-* The use of sexualized language or imagery and unwelcome sexual attention or
-  advances
-* Personal attacks
-* Trolling or insulting/derogatory comments, and personal or political attacks
+* The use of sexualized language or imagery, and sexual attention or advances of any kind
+* Trolling, insulting or derogatory comments, and personal or political attacks
 * Public or private harassment
-* Publishing other's private information, such as physical or electronic
-  addresses, without explicit permission
-* Other conduct which could reasonably be considered inappropriate in
-  a professional setting
+* Publishing others' private information, such as a physical or email address, without their explicit permission
+* Other conduct which could reasonably be considered inappropriate in a professional setting
 
-## Our Responsibilities
+## Enforcement Responsibilities
 
-Project maintainers are responsible for clarifying the standards of acceptable
-behavior and are expected to take appropriate and fair corrective action in response
-to any instances of unacceptable behavior.
+Core team members are responsible for clarifying and enforcing our standards of acceptable behavior and will take 
+appropriate and fair corrective action in response to any behavior that they deem inappropriate, threatening, offensive,
+or harmful.
 
-Project maintainers have the right and responsibility to remove, edit, or reject comments,
-commits, code, wiki edits, issues, and other contributions that are not aligned to this
-Code of Conduct, or to ban temporarily or permanently any contributor for other behaviors
-that they deem inappropriate, threatening, offensive, or harmful.
+Core team members have the right and responsibility to remove, edit, or reject comments, commits, code, wiki edits,
+issues, and other contributions that are not aligned to this Code of Conduct, and will communicate reasons for 
+moderation decisions when appropriate.
 
 ## Scope
 
-This Code of Conduct applies both within project spaces and in public spaces when
-an individual is representing the project or its community. Examples of representing
-a project or community include posting via an official social media account,
-within project GitHub, official forum or acting as an appointed representative at
-an online or offline event.
+This Code of Conduct applies within all community spaces, and also applies when an individual is officially representing
+the community in public spaces. Examples of representing a project or community include using an official e-mail
+address, posting via an official social media account, within project GitHub, official forum or acting as an appointed
+representative at an online or offline event.
 
 ## Enforcement
 
-Instances of abusive, harassing, or otherwise unacceptable behavior may be reported
-by contacting core team members. All complaints will be reviewed and investigated
-and will result in a response that is deemed necessary and appropriate to the circumstances.
-The project team is obligated to maintain confidentiality with regard to the reporter of
-an incident. Further details of specific enforcement policies may be posted separately.
+Instances of abusive, harassing, or otherwise unacceptable behavior may be reported by contacting core team members. All
+complaints will be reviewed and investigated promptly and fairly.
 
-Project maintainers who do not follow or enforce the Code of Conduct in good faith
-may face temporary or permanent repercussions as determined by other members of
-the project's leadership.
+All core team members are obligated to respect the privacy and security of the reporter of any incident.
+
+## Enforcement Guidelines
+
+Core team members will follow these Community Impact Guidelines in determining the consequences for any action they
+deem in violation of this Code of Conduct:
+
+### 1. Correction
+
+**Community Impact**: Use of inappropriate language or other behavior deemed unprofessional or unwelcome in 
+the community.
+
+**Consequence**: A private, written warning from core team members, providing clarity around the nature of the violation
+and an explanation of why the behavior was inappropriate. A public apology may be requested.
+
+### 2. Warning
+
+**Community Impact**: A violation through a single incident or series of actions.
+
+**Consequence**: A warning with consequences for continued behavior. No interaction with the people involved, including
+unsolicited interaction with those enforcing the Code of Conduct, for a specified period of time. This includes avoiding
+interactions in community spaces as well as external channels like social media. Violating these terms may lead to 
+a temporary or permanent ban.
+
+### 3. Temporary Ban
+
+**Community Impact**: A serious violation of community standards, including sustained inappropriate behavior.
+
+**Consequence**: A temporary ban from any sort of interaction or public communication with the community for a specified
+period of time. No public or private interaction with the people involved, including unsolicited interaction with those
+enforcing the Code of Conduct, is allowed during this period. Violating these terms may lead to a permanent ban.
+
+### 4. Permanent Ban
+
+**Community Impact**: Demonstrating a pattern of violation of community standards, including sustained inappropriate
+behavior, harassment of an individual, or aggression toward or disparagement of classes of individuals.
+
+**Consequence**: A permanent ban from any sort of public interaction within the community.
 
 ## Attribution
 
-This Code of Conduct is adapted from the [Contributor Covenant][homepage],
-version 1.4.0, available at
-[http://contributor-covenant.org/version/1/4/][version]
+This Code of Conduct is adapted from the [Contributor Covenant][homepage], version 2.1, available at
+[https://www.contributor-covenant.org/version/2/1/code_of_conduct.html][v2.1].
+
+Community Impact Guidelines were inspired by [Mozilla's code of conduct enforcement ladder][Mozilla CoC].
+
+For answers to common questions about this code of conduct, see the FAQ at
+[https://www.contributor-covenant.org/faq][FAQ]. Translations are available at
+[https://www.contributor-covenant.org/translations][translations].
 
-[homepage]: http://contributor-covenant.org
-[version]: http://contributor-covenant.org/version/1/4/
+[homepage]: https://www.contributor-covenant.org
+[v2.1]: https://www.contributor-covenant.org/version/2/1/code_of_conduct.html
+[Mozilla CoC]: https://github.com/mozilla/diversity
+[FAQ]: https://www.contributor-covenant.org/faq
+[translations]: https://www.contributor-covenant.org/translations