Separate client/server for load tests

Previously, the load testing script fired up a server, generated its own
data, and then hammered itself.  We want to test how the server
functions in production, so separate these two roles into a data
generator (which creates users etc. for load testing), and a traffic
generator (which opens many socket connections so wow using that data).

Additionally: change code that required session/user ID's to be
parseInt-able.  Sessions and Users can now have arbitrary strings as
ID's; useful for generating and destroying predictably isolated load
data.
Cleanup comment and debug logging
Always use native hangout notices; no persistence

Also, add a link to add the current event's URL to the message for
copy/pasting.
Merge branch 'load-simulator' into header-ui

Fix the configuration loading in light of the new lib/options parsing.

Conflicts:
	bin/unhangout-server