- add patch to fix runtime with modern twisted.web
- remove useless dependency on py-xml - it was successfully tested by
  maintainer with stock python xml package

While here:
- add NO_ARCH
- limit python version to 2.x
- modernize pkg-plist

Submitted by:	J.R. Oldroyd <fbsd@opal.com> (maintainer)
MFH:		2015Q3