Merge branch 'release_3.1.3' into devel

* release_3.1.3: (52 commits)
  ack fact scan messages
  making ldap user/group search fields into codemirror instances
  removing UI parsing for LDAP User and Group Search fields
  Allow exception view to accept all valid HTTP methods.
  Restore ability of parsing extra_vars string for provisioning callback.
  Fix up backup/restore role broken in f7a8e45809758322d9ee41c5305850dd70ed5faf
  Stop / start ansible-tower-service during restores
  value_to_python should encode lookup fields as ascii
  fix brace interpolation on standard out pane
  Adjust some hardcoded usages of 'awx' to use 'aw_user' and 'aw_group'.
  Pull Spanish updates from Zanata
  Temporarily grant awx user createdb role
  Stop giving ownership of backups to postgres
  don't display chunked lines'
  Add dropdown li truncation with ellipsis
  CTiT -> adhoc modules should allow the user to add new modules
  Remove task that was replacing the supervisor systemd tmp file
  Fix failing supervisorctl commands on RH-based distros
  Give ownership of the supervisor socket to awx
  Setting for external log emissions cert verification
  ...

awx/main/models/projects.py

@@ -204,6 +204,12 @@ class ProjectOptions(models.Model):
                     break
         return sorted(results, key=lambda x: smart_str(x).lower())
 
+    def get_lock_file(self):
+        proj_path = self.get_project_path()
+        if not proj_path:
+            return None
+        return proj_path + '.lock'
+
 
 class Project(UnifiedJobTemplate, ProjectOptions, ResourceMixin):
     '''