Update Contributing.md
Update Contributing.md

- add a table of contents
- adds the topics: 
-- Support Channels
-- Feature Requests
-- Bug Reports
-- Report a security vulnerability
-- Pull Requests
-- Writing Documentation and blogs
-- Issue Triage
-- Related Articles
- highlights code of conduct
- adds ways to contact us 
etc.

Signed-off-by: Tasha Drew <428a8f4391ea71add99cf4c8f8df7a5b6006c196@gmail.com>
nathenharvey/habitat,rsertelon/habitat,georgemarshall/habitat,rsertelon/habitat,georgemarshall/habitat,habitat-sh/habitat,habitat-sh/habitat,nathenharvey/habitat,habitat-sh/habitat,nathenharvey/habitat,rsertelon/habitat,georgemarshall/habitat,habitat-sh/habitat,nathenharvey/habitat,nathenharvey/habitat,georgemarshall/habitat,rsertelon/habitat,habitat-sh/habitat,georgemarshall/habitat,nathenharvey/habitat,rsertelon/habitat,habitat-sh/habitat,habitat-sh/habitat,georgemarshall/habitat,georgemarshall/habitat,georgemarshall/habitat,habitat-sh/habitat,rsertelon/habitat,rsertelon/habitat