(MAINT) Make user repl config dynamic

This commit modifies `user_repl.clj` and the sample `user.clj`
file to use a function instead of a var for the user-provided
config.

Prior to this, the config was read from disk as a var when the
REPL was first launched, and never re-loaded after that.  This
meant that doing a `reset` would not pick up changes you might
have made to the config files on disk; you needed to restart
the REPL to pick up those changes.

Now, the user config is acquired via a function call, which
means that your config files will be reloaded each time you
call `reset`.
(SERVER-151) Move environment fns from jruby-testutils to service

We originally defined some functions for interacting with the
environment cache state in jruby-testutils.  This commit moves
the logic into the `JRubyPuppetService` instead; this will be necessary
in order to wire up the HTTP endpoint, since we will only have
access to the service and not to the entire TK app.
(MAINT) Fix bugs in webrouting config

There were a few minor issues with the default config I provided
for the webrouting service.  This commit should fix them.
(MAINT) rename jvm-puppet-conf to puppet-server-conf
Merge pull request #278 from cprice404/maint/master/fix-webrouting-bugs

(MAINT) Fix bugs in webrouting config
Merge pull request #276 from cprice404/maint/master/dynamic-user-config

(MAINT) Make user repl config dynamic
Merge pull request #277 from cprice404/feature/master/SERVER-151-flush-env-cache-from-service

(SERVER-151) Move environment fns from jruby-testutils to service