Add makefile for building

This add's a makefile that automates:
- Getting/Installing go
- Setting up paths
- Installing dependencies, godep, etc.
- Building the binary

Review: @jrconlin r?
In this portion, its just declaring the path. ?= is used for conditional assignment of the local env var. In the build steps I'm going to attempt to make it optional such that you could symlink your own 'go' into this location to have it used instead of the downloaded one. (Not that this works properly yet, so I'm going to withdraw this PR till it does actually work)