Imported XFile from Torch3 + few fixes for compatibility
Few fixes to error.h
Added some comments about return values
Renamed XFile.cc to XFile.cpp
Added DiskXFile to a new computer-specific folder and made XFile compile properly
Fixed compile problem related to the changes in error.h
Minor cleanup
Add save/load functionalities to Observation and Action
Fix for the write method to write on a const pointer
Environment that exports to a file
Added external files to gitignore
Created abstractions for approximator functions
Moved NeuralNetwork to learning dir
Created a QFunction class that takes the place of NeuralNetwork in QLearningAgent and performs the Q-values computation
Added mapping methods
Some fixes in script for the new places of files
Some fixes in unit_test (not fully working yet)
Action now forces to declare nActions at allocation time
Sync with experimental branch
Resolve merge conflicts