Use breeze wrapper instead of mahout

[gyeongin]

Our current codebase uses mahout, which does not support in-place vector computation, leads to redundant memory allocation. For both performance and scalability, we should use other library supports in-place update. I investigated two netlib-java using libraries mtj and breeze, and mtj performed better than breeze. (In fact, breeze >= mtj > java-wrapped breeze)

[jsjason]

We decided to go with a breeze wrapper instead of mtj, due to license issues.