Added optimizer
Added optimizer package, which is focused in weight update
solved problems when saving/loading trainer objects, the optimizer was not being serialized/deserialzed properly
Adding optimizer options to tests of ann_base package
Minor change
Adding optimizer to map reduce
The optimizer is working well, and the first map reduce task is developed
Debugging MapReduce naive Lua implementation
Changed the API for loss functions: compute_loss and accum_loss methods
More for optimizer
Added conjugate gradient
Merged with master
Added Joan sanity check
Merged with optimizer