Move filtering private EDIDs from views to model manager.
Fix bugs in BaseForm._check_required_field()
*  Overwrite other validators error message.
*  Value 0 or False was treated as invalid.
Switch from function-based to class-based views.
Add get_absolute_url() method to EDID model.
Add a bit of validation to EDID upload form.
Changing EDID status on update is done by the form itself.
Work with public EDIDs only.