Add new arguments to run_tests
Add new arguments to run_tests

Execute unit tests and pep8 by default. Allow tests to be chosen in a more
additive fashion. Cleaned up unnecessary let statements and variable
defines.

Change-Id: I40676c5d0deda7bd3abc4bdadfd404f5909c166e
Signed-off-by: Jeff Peeler <d776211e63e47e40d00501ffdb86a800e0782fea@redhat.com>

cryptickp/heat,takeshineshiro/heat,rdo-management/heat,openstack/heat,cryptickp/heat,gonzolino/heat,NeCTAR-RC/heat,rdo-management/heat,NeCTAR-RC/heat,Triv90/Heat,redhat-openstack/heat,pshchelo/heat,citrix-openstack-build/heat,ntt-sic/heat,dragorosson/heat,dragorosson/heat,ntt-sic/heat,srznew/heat,dims/heat,Triv90/Heat,miguelgrinberg/heat,cwolferh/heat-scratch,jasondunsmore/heat,citrix-openstack-build/heat,rh-s/heat,steveb/heat,miguelgrinberg/heat,rh-s/heat,pshchelo/heat,jasondunsmore/heat,JioCloud/heat,maestro-hybrid-cloud/heat,rickerc/heat_audit,cwolferh/heat-scratch,pratikmallya/heat,rickerc/heat_audit,openstack/heat,gonzolino/heat,srznew/heat,steveb/heat,Triv90/Heat,JioCloud/heat,maestro-hybrid-cloud/heat,dims/heat,redhat-openstack/heat,pratikmallya/heat,varunarya10/heat,noironetworks/heat,varunarya10/heat,takeshineshiro/heat,noironetworks/heat