Restructured app
Merge branch 'develop' into feature/tests

* develop:
  Added thumbnails
  Added cut samples and scaled previews
  Added first draft of sample pictures
Switched from nosetests to py.test
Renamed format to size
Moved TODOs to it's own file
Merge branch 'feature/tests' into develop

* feature/tests:
  Moved TODOs to it's own file
  Renamed format to size
  Switched from nosetests to py.test
  Restructured app