PER-66: added new properties to groups in A/B experiment
PER-12: implemented loading of external configuration in A/B testing in synchronous mode
PER-78: started work on SASS support
PER-78: moved files to subdirs, added phpdoc documentation, switched to native PHP implemntation of Janus and minor fixes
PER-78: moved Sass classes to Wikia\Sass namespace
PER-78: connected AbTesting to new Sass implementation
Merge pull request #690 from Wikia/abtesting-css-enhamcements

A/B testing - adding support for pure CSS experiments