Add Moses dependency

[camillol]

The distro is missing the Moses package, and the included version of luarocks is unable to download it, so installation fails. This patch fixes the issue by adding a submodule for moses and installing it before nn.

This should also fix issues torch/torch7#1045 and torch/nn#1219.

The installation failure I got looks like this:

Missing dependencies for nn:
moses >= 1.0

Warning: Failed searching manifest: Failed loading manifest for https://raw.githubusercontent.com/torch/rocks/master: Error loading file: [string "/Users/camillol/.cache/luarocks/https___raw.g..."]:1: unexpected symbol near 'char(31)'
Warning: Failed searching manifest: Failed loading manifest for https://raw.githubusercontent.com/rocks-moonscript-org/moonrocks-mirror/master: Error loading file: [string "/Users/camillol/.cache/luarocks/https___raw.g..."]:1: unexpected symbol near 'char(31)'

Error: Could not satisfy dependency: moses >= 1.0