added limits include to fix compile error on ubuntu 12.04
fixed checkpoint_dir path
data parallelism using MPI
merge master into data_parallel
data parallelism
merge master with data_parallel branch
extract_representation_cpu refactoring
Merge pull request #12 from avdmitry/extract_representation_cpu_refactor

extract_representation_cpu refactoring
Merge branch 'master' of https://github.com/TorontoDeepLearning/convnet
fixed bug in row-wise sum
refactored loss functions, better grad check, minor edits
Merge pull request #8 from rdoroshenko/master

Added limits include to fix compile error on ubuntu 12.04
Update Makefile
Added video datahandler, support for rectangular images, minor edits.