Add glusterfs backend support

This patch allows to configure glusterfs backend options
by this formula.

Change-Id: Ib13a677b366cedb838103423d1481a0db44e4be2
diff --git a/.travis.yml b/.travis.yml
index b9d198d..8bb51f4 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -20,9 +20,11 @@
   - PLATFORM=epcim/salt-formulas:saltstack-ubuntu-xenial-salt-2016.3 OS_VERSION=pike SUITE=server_cluster
   - PLATFORM=epcim/salt-formulas:saltstack-ubuntu-xenial-salt-2016.3 OS_VERSION=pike SUITE=server_single
   - PLATFORM=epcim/salt-formulas:saltstack-ubuntu-xenial-salt-2016.3 OS_VERSION=pike SUITE=share_nexenta
+  - PLATFORM=epcim/salt-formulas:saltstack-ubuntu-xenial-salt-2016.3 OS_VERSION=pike SUITE=share_glusterfs
   - PLATFORM=epcim/salt-formulas:saltstack-ubuntu-xenial-salt-2017.7 OS_VERSION=pike SUITE=server_cluster
   - PLATFORM=epcim/salt-formulas:saltstack-ubuntu-xenial-salt-2017.7 OS_VERSION=pike SUITE=server_single
   - PLATFORM=epcim/salt-formulas:saltstack-ubuntu-xenial-salt-2017.7 OS_VERSION=pike SUITE=share_nexenta
+  - PLATFORM=epcim/salt-formulas:saltstack-ubuntu-xenial-salt-2017.7 OS_VERSION=pike SUITE=share_glusterfs
 
 before_script:
   - set -o pipefail