updates contributing info, readme
add docs for new helpers
add credit to Dan Harper to each individual helper document.
adds plugins and extensions pages
moves, updates some includes
renames, organizes data files
adds contributing.md
removes .hbs from helpers docs files
many formatting, grammar and structural updates
updates side navigation for helpers
Merge branch 'origin/master'

Conflicts:
	bower.json
	src/templates/layouts/default.hbs
adds .gitattributes to force lf line endings
Merge branch 'origin/master'
moves templates to project root