Merge pull request #2 from CybOXProject/newrevision

revision to docs
Update index.md
Indent every header on background page by one level
More cleanup
Fix some more links and other assorted cleanup
Update index.md

Remove reference to "Washington and Boston only"
Moved the CybOX Object Selection suggested practices over from the STIX doc site and made changes to the bolded end practice statement.
Clean up markdown and fix links
Update _config.yml
Make file path suggestions more definitive