refactored Dom.addClass and Dom.removeClass to use Strings.addToList etc. functions
added test cases
Merge branch 'howling-mad' of github.com:alohaeditor/Aloha-Editor into hm-classes-refactoring
refactored usage of Dom.addClass
Parrot!
Merge pull request #1215 from cprerovsky/hm-classes-refactoring

Dom.addClass + Dom.removeClass refactoring
Don't allow adding duplicates through addToList()
Shorten 'uniqueArray' to 'set'
Improve function signature for modifyClassList()
Correct some function annotations
list -> lists
Correct list transformation collapsed selections
Trim all types of whitespaces with Strings.words()
Update breaking tests
Lists.unformat
Correct boundaries while processing list.unformat()
Revert "Don't allow adding duplicates through addToList()"

This reverts commit 72e58a0f3467196f68a65cd0207115eae0f23d53.