gplazma-xacml: Add handling of GID returned by GUMS in gPlazma2 XACML plugin

    Patch: https://rb.dcache.org/r/7061/
    Acked-by: Albert Rossi <arossi@fnal.gov>
    Target: trunk
    Require-book: no
    Require-notes: yes

RELEASE NOTES:
gplazma-xacml: Add handling of GID returned by GUMS in gPlazma2 XACML plugin
(cherry picked from commit 40356b5bfbc3aab0f81fbb5434181bbeae974a16)
Merge pull request #962 from DmitryLitvintsev/fix/2.6/gums

gplazma-xacml: Add handling of GID returned by GUMS in gPlazma2 XACML pl...