This script quiently depended on being under a GOPATH, and failed
completely when it was not. This change sorts the input (to make
comparing results easier) and operates on files, rather than packages
until the last moment when we add back the package prefix.
Verified by instrumenting the code and comparing runs inside and outside
of GOPATH.
This commit is an initial pass at providing an admission API group.
The API group is required by the webhook admission controller being
developed as part of https://github.com/kubernetes/community/pull/132
and could be used more as that proposal comes to fruition.
