Stop when SOURCE_FILE blank

If you mess up the git trees, SOURCE_FILE can be blank.  This leads to
a confusing cp error.  Make the error a bit more helpful
Merge pull request #34 from ianw/error-no-source

Stop when SOURCE_FILE blank
Upstream ceilometerclient package

Changes required for building ceilometerclient packages are merged
upstream, so switch there.
have the packstack build working w/o having to maintain a spec file
had to merge my modified spec that can exclude docs, pulling spec from redhat-openstack repo's
Merge pull request #37 from ianw/ceilometer-main

Upstream ceilometerclient package
Merge pull request #38 from weshayutin/packstack

Packstack