Grunt express server isn't necessarily the most accurate name

I know this is a minor nit-pick, but any node server, no, actually, any webserver that can be spawned and prints to stdout could be used with this task.

What more generic names would you guys suggest?

I guess that we could even plead to becoming something like a `grunt-contrib-server` because this is the only task that works correctly with `grunt-contrib-watch`.

Ideas? @ericclemmons @paulpflug @justcfx2u