Include .editorconfig

http://editorconfig.org/
Refined .editorconfig
Use* global rules with exceptions as needed
'root' repo end 'insert_final_newline = true'
Fixes #7661
explicit callout in readme for building static assets; fixes #7632
shoutout to editorconfig in readme
'root' folder .editorconfig code guide updates
'less' folder .editorconfig code guide updates
'js' folder .editorconfig code guide updates
'docs' folder .editorconfig code guide updates
- changed comments
- added hover and focus state for [href] color variations