Add pagure git commit consumer
    
    We are once again misusing the item to carry additional information.
    I'd really like to be able to have libtaskotron take the arbitrary input
    (and I think we will have to do this sooner than later), but it is out
    of the scope for this diff
    
    This also fixes a heisenbug in testing, where depending on the order in
    which the tests ran, the dist_git_commit/pagure_git_received were getting
    either [x86_64] or [i386, x86_64] as valid arches, because some of the
    testsuites change the default config value and do not clean up.
    
    Differential Revision: https://phab.qa.fedoraproject.org/D1110