Updating the Dockerfile to build v0.5.0
Switching to Ubuntu 13.10, dropping Go install, using ruby 2.0

and holy moly is the image 1/3 the size it was with 12.04 (???)
Installing node so that all supported interpreters are present
Switching to preferred stackbrew/ubuntu image
Changes per feedback from @rafecolton
Merge pull request #64 from modcloth-labs/updating-dockerfile

Updating dockerfile