Optimize Dockerfile by combining RUN layers (final image ~50mb smaller)
Update to Go 1.3.3
Adding checksum for go tarball because we make good decisions
Making Dockerfile a little smaller and more readable

Removing go src, pkg files and deppy binary after building.  Also
reorganizing by putting the `&&`s at the beginning of the lines for
readability
Fixing test related to parsing the git branch
Merge pull request #151 from rafecolton/optimize-dockerfile

Optimize Dockerfile (final image ~130 smaller)