OOZIE-1550 Create a safeguard to kill errant recursive workflows before they bring down oozie (rkanter)

git-svn-id: https://svn.apache.org/repos/asf/oozie/trunk@1542114 13f79535-47bb-0310-9956-ffa450edef68
Merge remote branch 'origin/trunk' into trunk
Merge remote branch 'origin/trunk' into trunk-gd
Merge remote branch 'origin/trunk-gd' into fb-YAHOO-308-trunk-gd