(PUP-3642) Remove environment name from URL path

This commit makes some changes to the indirector network layer
such that the environment name is no longer a part of the main
URL path structure.  This will allow us to have a more finite URL space
and run Puppet in the same webserver with other apps, without
worrying about URL collisions.  Instead, the environment becomes a query
parameter.
Merge pull request #3412 from cprice404/feature/master/PUP-3642-remove-env-from-url-path

(PUP-3642) Remove environment name from URL path