Fix issue2551129 - Template not found return 500 and traceback Handle traceback caused when requested @template is not found. Moved scope of try to include call to self.selectTemplate. Patch provided by Cedric Krier. Additional patch to make this case return 400 error since it is a client caused error. Test case added.

#!/usr/bin/env python
import sys
import roundup

from roundup.demo import main

sys.exit(main())