Adding Snockets compilation of js, cs and ts files

This patch adds snockets support to sails via asset-rack. The major issue this addresses is dependency management in client side code.

From my perspective `#= require "my_dependency"` has always been very readable, predictable and concise.

But I wonder if there are different camps on this. What's the consensus?

originally https://github.com/balderdashy/sails/pull/375