Upgraded group operators to 1.3 version.

diff --git a/mod/group_operators b/mod/group_operators
index ce71a5441f2b03074f5d2dd631ead271af4dc68b..f3983fbf70975112e2f6aca716f10ebc402d43f0 160000 (submodule)
--- a/mod/group_operators
+++ b/mod/group_operators
@@ -1 +1 @@
-Subproject commit ce71a5441f2b03074f5d2dd631ead271af4dc68b
+Subproject commit f3983fbf70975112e2f6aca716f10ebc402d43f0