Redesign of ImportView
Refactored upload receiver into the import view
Put input stream from the upload to csv reader
Deleted CSVUploader
Deleted unnecessary CSVHandler method.
Changed CSVTest due to changes of the CSVHandler api.
Persistierung des Eltern-Objekts wieder einkommentiert.
Removed createParentObjectsFromCSV.
Parent objects are created together with student objects now since all
parent information are in the same csv as the student information.
Deleted test method that tested the creation of parent objects.
Added try catch to check parent objects creation.
Persist students in importViewModel.
Added null check for parent objects.
Limit max file size of the uploaded file
Merge pull request #206 from jidel/issue#188#187#196

Issue#188#187#196