Clarify flags for info server startup

Make a distinct flag to enable/disable the server.  Comment on the address
flag.
Set kubelet -address flag to 0.0.0.0 via salt

Currently it binds to the eth0 IP only, this includes localhost.  The flag
default is localhost only, but we need it looser than that.
Merge pull request #814 from thockin/cleanups3

Clean up the -address flag in kubelet