Added minified js support
Support for promise.

A cubicle can now return Promise instead of actual worker.
Allow changing the name of "Cubicle" function.

If user doesn't like the name "Cubicle", they can change the name just
by changing the last word. But should be done everyt-ime the version
gets updated.
Named "cubicle" variables to worker.

As what was being called cubicle was actually worker, renamed as such.
Renamed functions from "export"/"import" to announce and invite

The latest convention is call these functions "announce" and "invite"
respectively. Although these are variable names and can be called
absolutely anything.
Make code pass jslint with tolerate plusplus.

Except ++, every jslint instructions are followed.
changed function name to "cubicle" from "Cubicle"

As jslint suggests using small letter for normal function, and
capitalize only if it is a constructor. Consumer of Cubicle.js is also
going to get same error if name is left as it is ("Cubicle").
Change readme to reflect change name of function from "Cubicle" to "cubicle"