Skip pip mirrors for RHEL

The RHEL6 version of pip doesn't have support for mirrors, so skip
asking for them.

Change-Id: Iaf2900067bb4b41f88d8fe82ea16b6b53d6bcc60
Add support for GlusterFS Cinder driver

The GlusterFS volume driver can be used with Cinder by setting the
following in localrc:

CINDER_DRIVER=glusterfs
CINDER_GLUSTERFS_SHARES="127.0.0.1:/vol1;127.0.0.1:/vol2"

Shares are <host>:<volume> and separated by semicolons.

Change-Id: Iaa105233c9fce8d8fda0a9ea447e045b8d010db7
Merge "Skip pip mirrors for RHEL"
Merge "Add support for GlusterFS Cinder driver"