1.1.17-0.1.rc4 - Update for new upstream tarball
    
    ... for release candidate: Pacemaker-1.1.17-rc4,
    for full details, see included ChangeLog file or
    https://github.com/ClusterLabs/pacemaker/releases/tag/Pacemaker-1.1.17-rc4
    
    Add an imposed lower bound for glib2 BuildRequire
    
    Signed-off-by: Jan Pokorný <jpokorny@redhat.com>