Update readme

[khanzadyan]

Update the information in the readme file and change/remove the broken links.

[stas-fomenko]

Also need to add limitation related to Action: XML Attachment to JSON.
It would not work on local agent because local agents do not support attachments

[ZainNoor99]

CDoD

Component development prerequisites:

• Development team has all needed requirements
• Access to the needed service with all needed permissions is granted
• No open tasks that could block Component development process
• The E.io’s GitHub repository must be checked if there is another implementation of the component under development. If it exists, new repository should not be created.
• Component architecture should be discussed and approved before start coding
  Development:
• Code is written and formatted in accordance with the Styling guide
• Code (incl. configs, test samples, environment variables etc.) MUST NOT contain any sensitive data like passwords, tokens, API keys etc.
• Component logs does not contain any sensitive data (credentials, input/output requests, Environment variables)
• Code is covered with unit tests
• Component code is covered with integration tests (optional)
• Triggers/actions comply with OIH patterns
• Documentation (README.md file in the Github) is 100% ready.
• CI is set up
• All development branches are reviewed
  After QA:
• All development branches are merged into master branch
• Sprint review preparation is finished (demo flow is built)
  QA:
• Test cases for the component are ready at the TestRail.
• Functional testing is finished.
• Regression testing is finished (optional).
• Component is deployed to the production stage (app.elastic.io) and/or other required stage.
• Component has a proper access level
• Smoke test is finished
• Release notes are done
• Component Roadmap is updated.
• Component spreadsheet is updated