Fix up tempest conf settings

The tempest api.volume.test_volume_types test won't
work with non-default drivers configured for cinder's backend
any more.  The reason is that we create a type using capability
scheduler keywords in the extra-specs for the test;
(vendor_name and storage_protocol).  The result is the extra-spec
uses the filters: "vendor_name=Open Source" and
"storage_protocol=iSCSI", but for example if you have another backend
say SolidFire, EMC, NetApp, IBM etc the capabilities filter will fail
the create with a "No valid host available".

This is intended to work by simply setting these values in your
tempest.conf file.  That's fine, however upon setting this up
in my localrc I found that the tempest config variables being
set via devtsack were never picked up

Currently devstack doesn't use the same variable names for
configuration variables as tempest expects. Devstack is using
the variable "TEMPEST_CONF" however the Tempest project is
expecting the variable "TEMPEST_CONFIG", so currently the
devstack lib/tempest rc variables are never picked up by
tempest properly.

This change modifes devstack's naming of TEMPEST_CONF, my though
being that since this doesn't work in devstack currently
that changing it here would be better than changing it in Tempest
where it's possible people had their own custoizations already
outside of devstack.

In addition this change creates rc variables in devstack to actually
set these via devstack.  The idea here is that Cinder 3'rd party testing
needs to be a simple devstack config and run stack.sh.  By fixing up
the configuration file variable naming and adding the variables for
the vendor and protocol settings that's now possible.

An example localrc for a custom config is shown below.  The example
sets the tempest config file to /etc/tempest/tempest.conf, and
configures tempest to use the SolidFire driver as the cinder backend.

TEMPEST_VOLUME_VENDOR ==> tempest.conf.volume_vendor
TEMPEST_STORAGE_PROTOCOL ==> tempest.conf.storage_protocol

relevant example localrc entries:
  TEMPEST_CONFIG=/etc/tempest/tempest.conf
  TEMPEST_CONFIG_DIR=/etc/tempest
  TEMPEST_VOLUME_DRIVER=solidfire
  TEMPEST_VOLUME_VENDOR="SolidFire Inc"

***NOTE***
storage_protocol and vendor_name MUST match what the backend device reports from
get capabilities.

Change-Id: I28dfa90c877b27f5d4919f2748fae092bb2f87fa
Closes-Bug: 1271781
Add support for Gantt

Gantt is the new breakout of the scheduler code from the Nova
source tree.  These changes allow devstack to install/configure/startup
gantt as the scheduler service for openstack.

Change-Id: Ia2b6001f5ccf2469ee9fdee67564c9a915a13862
Merge "Add support for Gantt"
Merge "Fix up tempest conf settings"