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
from __future__ import print_function
import zlib, base64, sys
print(base64.encodestring(zlib.compress(sys.stdin.read())))