Add a Makefile

Maybe I am alone in my distaste for the go way fo building.  It's very opaque
and opinionated.  I do not think it is reasonable to demand a user put code in
a particular organization to use it or to require environment variable
fiddling (really?  in 2014?).  I also don't think hand-rolled scripts give a
pleasant experience.

This simple Makefile obsoletes two scripts and a config-script.  It should
provide a pretty-much identical experience.

make - build all binaries
make clean - clean up
make test - run tests
make kubelet - just build kubelet
make test WHAT=pkg/kubelet - test pkg/kubelet/*