Fix UnicodeEncodeError for Manila

TASK: [manila | Copying over manila.conf] fails while
deploying Manila ubuntu binary image with the following
error.

UnicodeEncodeError: 'ascii' codec can't encode character
u'\u2018' in position 313: ordinal not in range(128)

The reason was use of non-ascii character <``> in manila.conf.j2
which is replaced by <''> in this patch to fix the issue.

Change-Id: Ic26a5829ed700179997c7c06836fd581a67a6777

ansible/roles/manila/templates/manila.conf.j2

@@ -10,7 +10,7 @@ my_ip = {{ hostvars[inventory_hostname]['ansible_' + api_interface]['ipv4']['add
 # Values are conf groupnames that contain per manila-share service opts.
 enabled_share_backends = generic
 
-# Manila requires ‘share-type’ for share creation.
+# Manila requires 'share-type' for share creation.
 # So, set here name of some share-type that will be used by default.
 default_share_type = default_share_type