cleanup to ProjectQuasiNewton, etc.
Merge branch 'master' of github.com:dlwh/breeze

Conflicts:
	learn/src/main/scala/breeze/optimize/PQN.scala
	learn/src/main/scala/breeze/optimize/ProjectedQuasiNewton.scala
	learn/src/main/scala/breeze/optimize/SPG.scala
	learn/src/main/scala/breeze/optimize/SpectralProjectedGradient.scala
	learn/src/test/scala/breeze/optimize/PQNTest.scala
	learn/src/test/scala/breeze/optimize/ProjectedQuasiNewtonTest.scala
	math/src/main/scala/breeze/optimize/PQN.scala
	math/src/main/scala/breeze/optimize/SPG.scala
	math/src/test/scala/breeze/optimize/PQNTest.scala