OpenNMT-py v0.3

Now requires Pytorch 0.4.1

Multi-node Multi-GPU with Torch Distributed

New options are:
-master_ip: ip address of the master node
-master_port: port number of th emaster node
-world_size = total number of processes to be run (total GPUs accross all nodes)
-gpu_ranks = list of indices of processes accross all nodes

-gpuid is deprecated

See examples in https://github.com/OpenNMT/OpenNMT-py/blob/master/docs/source/FAQ.md

Fixes to img2text now working

New sharding based on number of examples

Fixes to avoid 0.4.1 deprecated functions.