2012.01.05, Version 0.0.8

* added mp_lib property, so people can segment by library

2012.01.05, Version 0.0.7

* added unit tests
* people.increment() only prints error message if debug is true

2012.01.01, Version 0.0.6

* added engage support
	* people.set()
	* people.increment()
	* people.delete_user()

* deprecated old constructor: require("mixpanel").Client(token)

* added new constructor: require("mixpanel").init(token)
