Parametrize manila options

Add possibility to set manila volume name
on cluster level. Moreover added apache wsgi
module to manila apache site definition since it is mandatory for
manila-api to work as expected

Change-Id: I5b9c5dacd298cf1d7926568cb169bdcf5d7b6838
Related-PROD: PROD-21340
diff --git a/apache/server/site/manila.yml b/apache/server/site/manila.yml
index cecf1d4..3080d1d 100644
--- a/apache/server/site/manila.yml
+++ b/apache/server/site/manila.yml
@@ -12,6 +12,8 @@
     server:
       enabled: true
       default_mpm: event
+      modules:
+        - wsgi
       site:
         manila:
           enabled: false