Moved code to get classes from 'server' (json) to its own factory.
Moved factory to get classes to its own module.
Removed duplicate code.
Corrected path to controller in comment.
Moved dataGetter module to its own file.

Not sure if app/controllers is the right place.
Made dataGetter available in the workspace.
Indentation fix.
A subject may now contain a comment.
Added comment section to subjects on workspace.
Added comments to classes.json.
Merge pull request #37 from swp14-gsb/getClasses

Subjects now may have comments.