(WIP) Added Multi-layer perceptron (MLP)

Seeking to finalize MLP
Fixed some typos
A lot of improvements

1) Optimization_method parameter for selecting any scipy optimizer
2) SGD is also supported
3) Improved minibatch creation using scikit's gen_even_slices (much
faster)
4) Support of loss functions
squashed last 35 commits
squashed last 25 commits
Major cleaning
update
major changes to MLP
fixed fixes.py
fixed mlp_test
Massive changes
updated doc
Added ReLu support. Improved test cases
Tonnes of updates
update doc
fixes
updated derivatives
Inlined several methods
updated loss function
Updates