OOZIE-1339 Implement SLA Bootstrap Service and fix bugs in SLACalculator (virag)

git-svn-id: https://svn.apache.org/repos/asf/oozie/trunk@1491333 13f79535-47bb-0310-9956-ffa450edef68
Merge remote branch 'origin/trunk' into trunk
Merge remote branch 'origin/trunk' into trunk-gd