Updating requirements.txt for Travis-CI.
Updating requirements.txt for Travis-CI.

citrix-openstack-build/pecan,pecan/pecan,ryanpetrello/pecan,citrix-openstack-build/pecan,jimrollenhagen/pecan,jdandrea/pecan,jdandrea/pecan,ryanpetrello/pecan,pecan/pecan,StackStorm/pecan,StackStorm/pecan,jimrollenhagen/pecan