moving the github integration with pull requests
into a function so we can continue to service opnfv-tht
and also service opnfv-puppet-tripleo with the same code

opnfv-puppet-tripleo-pr: 3

Change-Id: Ief2b1e7309defce9ed2029f6baade3c1371b7d96
Signed-off-by: Dan Radez <dradez@redhat.com>