LBFGS
q
Merge remote-tracking branch 'origin/dbtsai-LBFGS' into dbtsai-LBFGS

Conflicts:
	mllib/src/main/scala/org/apache/spark/mllib/optimization/LBFGS.scala
	mllib/src/test/scala/org/apache/spark/mllib/optimization/LBFGSSuite.scala