Dart language support
Merge branch 'master' of github.com:dikmax/highlight.js into dart

Conflicts:
	AUTHORS.en.txt
	AUTHORS.ru.txt
Dropped all custom relevance from dart.js
Fixed link parsing in markdown.
Rearranged Dart snippet and class reference.
Merge branch 'dart'

Conflicts:
	AUTHORS.en.txt
	AUTHORS.ru.txt
Merge branch 'master' of github.com:isagalaev/highlight.js