features/compress: Add mem accounting support for compress

Change-Id: I89a7a4cd64ef65ad3bab180d66797a62b4e1e195
BUG: 923540
Signed-off-by: Pranith Kumar K <pkarampu@redhat.com>
Reviewed-on: http://review.gluster.org/7320
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Prashanth Pai <ppai@redhat.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>