Rename get_or_add_user_role

get_or_add_user_role is specific to adding a role on a project.
Rename it to get_or_add_user_project_role to allow room for adding a
domain specific role function.

Change-Id: I999308098d22be9800578ae67144a3b687fbc3be
diff --git a/functions-common b/functions-common
index d3b3c0c..6beb670 100644
--- a/functions-common
+++ b/functions-common
@@ -913,9 +913,9 @@
     echo $role_id
 }
 
-# Gets or adds user role
-# Usage: get_or_add_user_role <role> <user> <project>
-function get_or_add_user_role {
+# Gets or adds user role to project
+# Usage: get_or_add_user_project_role <role> <user> <project>
+function get_or_add_user_project_role {
     # Gets user role id
     local user_role_id=$(openstack role list \
         --user $2 \