Install nsinit on hosts.
Fix proxy error condition and simplify method

Add new minion proxy test case.
Address remaining comments from #756

Rename Encoding to Codec, Versioning to ResourceVersioner.  Add
GoDoc.  Add Delete(key, recursive) to EtcdHelper
Merge pull request #808 from smarterclayton/minion_proxy_test

Fix proxy error condition and simplify method
Merge pull request #806 from smarterclayton/follow_up_to_encoding_abstraction

Address remaining comments from #756
Merge pull request #803 from brendandburns/nsenter

Install nsinit on hosts.