Development

recent changes:
- #146 IDE - Remove Draw new Image
- #148 Rename levels
- set default program as last program at the beginning correctly
- set last program after program is deleted correctly
- #147 Move all images to xcasset
- removed old unused files in project's root FS directory
- fix some compile warnings
- using md5 filehash instead of random UUID in filename of imported and created images
- #140 fixed reloading issue by Andreas
- new tests for ProgramTableViewController
- combobox elements for bricks
- gesture handler for SoundsTableViewController and show and determine duration of a sound
- fix toolbar problems
- #129 allow deleting all objects except background object
- new tests for program class
- better Fullscreen effect at forumWebViewController by Marc
- #120 scrollview when tapping on Images in LooksTableViewController
- hide unavailable bricks for bg objects