Add first draft general README:
Add first draft general README:

This is a readme providing general information about TrueOS and its umbrella projects. It contains:
- Links to all TrueOS documentation.
- Description of where to file GitHub issues with a link to the handbook with detailed instructions on how to file a issue.
- Links/descriptions of all community chat channels.
- Links/descriptions of all social media accounts.
trueos/pcdm,trueos/pcdm,trueos/pcdm