nsqd: HTTP versioning

* drop response wrapper
* use correct HTTP codes
* use Accept header to indicate version
nsqd: require post for mutating v1 HTTP endpoints
Merge pull request #330 from mreiferson/http_refactor_330

nsqd: http api inconsistencies
starting to flesh out ideas
more thoughts
more empty ideas
closer to a draft server side
first pass of prototype auth daemon
validate matching
test auth file
add in authorization handling
pass through auth parameters, add tls flag
woah it works
return ok response when authorization completes
use %q for quoted error strings; PUB auth
auth for MPUB
cleanup
add missing flag for authd on nsqd command line
more portable mktemp usage
skip go builds in nsqadmin (just has a python file)