glusterfs.spec.in: resync with Fedora glusterfs.spec

cherry-pick from master, including commits:
 5d3b478e76f1015b11bfd7d48465ab12a4f0737e
 fd407a4f5cdb869dc52efe8fc9e1d284f60f5992
 6f6789884227b8260f140c39c063d77b0516af97
 84f5e4b354526fbb7f0665345816e81c81245c8f
 2398e1e0da61f4ec5f209c704e037b54b5c249e1

Resync with Fedora's glusterfs.spec

To build a set of RPMs:
 % ./autogen.sh
 % ./configure --enable-fusermount
 % make dist
 % cd extras/LinuxRPM && make glusterrpms

Updated rpm.t

BUG: 819130
Signed-off-by: Kaleb S. KEITHLEY <kkeithle@redhat.com>
Change-Id: Ib73be0fbb7ee16a5c41b4f7c7a3f66d0224bfe6c
Reviewed-on: http://review.gluster.org/4725
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Anand Avati <avati@redhat.com>