Allow SystemEvents to run command as application owner

Change-Id: I80b021363aacda3e9bedd3e8b25a93d21de73ac5
Merge commit 'refs/changes/26/326/7' of ssh://gerrit.tuleap.net:29418/tuleap into tuleap-stable-master

* ssh://gerrit.tuleap.net:29418/tuleap:
  Allow SystemEvents to run command as application owner
Tuleap 5.11.99.19