Issue #171

server limit the number of webUI clients that can attach.

This will probably always be "0" or "unlimited", but allows ops to set a max limit for WebUI clients. (realistically, probably 3 is more than enough)

@crankycoder r?
![HATERS GONNA HATE](http://img3.wikia.nocookie.net/__cb20131024193753/degrassi/images/6/6e/Arthur-hatersgonnahate.gif)