Test fix and refactored playlist resource.
Moved Role parsing to Role class instead of UsersTable.
Playlist refactoring for future use.
Removed final modifier from model user, for future use.
Created ModelBuilder to make automatic parsing of form parameters possible.
Changed ModelBuilder to throw service exception instead of multiple different exceptions.
Removed white space.
Refactored user resource edit to use model builder.
Fixed broken role changing and refactored user creation to use model builder.