Issue #5: Introduce elementary CONTRIBUTING doc

CONTRIBUTING.md

@@ -0,0 +1,101 @@
+# Contributing Guide 
+
+There are many ways to be an open source contributor, and we're here to help you on your way! You may:
+
+* Propose ideas in our discussion forums
+* Raise an issue or feature request in our issue tracker
+* Help another contributor with one of their questions, or a code review
+* Suggest improvements to our Getting Started documentation by supplying a Pull Request
+* Evangelize our work together in conferences, podcasts, and social media spaces.
+
+This guide is for you.
+
+## Development Prerequisites
+
+| Requirement | Tested Version | Installation Instructions
+|-|-|-|
+| Go | 1.17.6|[go.dev](https://go.dev/doc/tutorial/compile-install)
+| Mage | 1.12.1|[magefile.org](https://magefile.org/)
+
+### Go
+
+The `did-sdk` is written in Go, a modern, open source programming language. 
+
+You may verify your `go` installation via the terminal:
+
+```
+$> go version
+go version go1.17.6 darwin/amd64
+```
+
+If you do not have go, we recommend installing it:
+
+#### MacOS
+
+##### Homebrew
+```
+$> brew install go
+```
+
+### Mage
+
+The `did-sdk` build is run by Mage.
+
+You may verify your `mage` installation via the terminal:
+
+```
+$> mage --version
+Mage Build Tool 1.12.1
+Build Date: 2021-12-15T21:00:02Z
+Commit: 2f1ec40
+built with: go1.17.6
+```
+
+#### MacOS
+
+##### Homebrew
+
+```
+$> brew install mage
+```
+
+## Build 
+
+```
+$> mage build
+```
+
+## Test
+
+```
+$> mage test
+```
+
+## Communications
+
+### Issues
+
+Anyone from the community is welcome (and encouraged!) to raise issues via GitHub Issues.
+
+### Discussions
+
+Design discussions and proposals take place on GitHub Discussions. We advocate an asynchronous, written debate model - so write up your thoughts and invite the community to join in!
+
+### Continuous Integration
+
+Build and Test cycles are run on every commit to every branch on [CircleCI](https://app.circleci.com/pipelines/github/TBD54566975/did-sdk?filter=all).
+
+## Contribution
+
+We review contributions to the codebase via GitHub's Pull Request mechanism. We have the following guidelines to ease your experience and help our leads respond quickly to your valuable work:
+
+* Start by proposing a change either in Issues (most appropriate for small change requests or bug fixes) or in Discussions (most appropriate for design and architecure considerations, proposing a new feature, or where you'd like insight and feedback)
+* Cultivate consensus around your ideas; the project leads will help you pre-flight how beneficial the proposal might be to the project. Developing early buy-in will help others understand what you're looking to do, and give you a a greater chance of your contributions making it into the codebase! No one wants to see work done in an area that's unlikely to be incorporated into the codebase.
+* Fork the repo into your own namesapce/remote
+* Work in a dedicated feature branch. Atlassian wrote a great [description of this workflow](https://www.atlassian.com/git/tutorials/comparing-workflows/feature-branch-workflow)
+* When you're ready to offer your work to the project, first:
+* Squash your commits into a single one (or an appropriate small number of commits), and rebase atop the upstream `main` branch. This will limit the potential for merge conflicts during review, and helps keep the audit trail clean. A good writeup for how this is done is [here](https://medium.com/@slamflipstrom/a-beginners-guide-to-squashing-commits-with-git-rebase-8185cf6e62ec), and if you're having trouble - feel free to ask a member or the community for help or leave the commits as-is, and flag that you'd like rebasing assistance in your PR! We're here to support you.
+* Open a PR in the project to bring in the code from your feature branch.
+* The maintainers noted in the `CODEOWNERS` file will review your PR and optionally open a discussion about its contents before moving forward.
+* Remain responsive to follow-up questions, be open to making requested changes, and...
+* You're a contributor!