Update README.md
[dev] use LESSCSS, pass JSHINT

	renamed:    css/dev/mycss.css -> css/dev/mycss.less
	modified:   index_dev.html
	modified:   js/dev/mwcardex.js

removed need for filter-group
color highlights are defined with less mixin
Merge branch 'master' of github.com:leesei/mwcardex into gh-pages
Merge branch 'gh-pages' of github.com:leesei/mwcardex into gh-pages

Conflicts:
	css/dev/mycss.less