Minimal changes on Comments

Minimal changes on Comments
Handle empty alias for added subjects

If the user adds a subject without an alias, the uri is used.
workspaceCtrl is mainCtrl now.
Removed functions from it that will be handled by other controllers in the future.
New Controller: SubjectCollectionController, Merged addSubject into the new controller.
alias prefixes for Object properties removed #40
New Controller: SubjectInstanceCtrl.
New Controllers: propertyCollection & propertyInstance.
Moved ObjectProperty Logic into own directive, template and controller.
Fixed CSS that we destroyed the way along.
Fixed startPoint and highlighting of subjects (now with an Event!).
Merge branch 'feature/new-controller-structure' into develop
Removed unneeded Javascript, related to highlighting subjects.
Made Subjects draggable. (Code taken from feature/draggable branch)
Improved result area.
Merge branch 'feature/new-layout' into develop
Added event to re-enable translation
Renamed service to get available classes.
Moved translation process into own services
Made AvailableClassesService known to propertyCollection.
Changed variable names in propertyCollection.

Removed ‘$parentSubject’ since it would now be used in only two places
and therefore, in my opinion, just complicates things.

Also renamed ‘$selectedProperties’ to ‘selectedProperties’, since
AngularJS uses the ‘$’ prefix to indicate AngularJS internal stuff, so
no ‘$’ for us.