Set types -- Added custom manager.

Manager provides get_settype_config_dict() method that returns a dictionary with set type instance settings. Related to #126.
Set types -- Added Javascript enhancements to admin.

Configured fields are now dynamically shown/hidden from the admin form when users change the set type selection. Tested in Django admin. Needs testing in Django Suit. Related to #126.
Set types -- Added Suit support for admin enhancements.

Added support for when suit is installed and a suit tab is used to show a field that is configured to be hidden in the set type. This tab gets hidden now as well. Resolved #126.