Added instanceOf method for classes.

Useage would be on instances created as such:
`instance:instanceOf(Class)`

* Will return true if argument is a superclass.
* Will return true if argument is a mixin.
Added a Travis-CI file for continuous integration.

Put in place so we have a fancy Travis-CI banner, and to quickly deploy and test sunclass on an arbitrary machine to see if everything is working.
Fixed rockspecs file

Rockspecs is used for luarocks and defines all the settings of the luarocks package. For people who are using luarocks, you can install sunclass just by calling `luarocks install sunclass`.
Added generic unit tests

Created some generic unit tests that can be ran with "busted".
http://olivinelabs.com/busted/

Unit tests:
* Generic classes and class methods
* Inherited classes and inherited methods
* Mixins and mixed classes.
Merge branch 'master' of https://github.com/qwook/sunclass

Conflicts:
	rockspecs/sunclass-1.0-0.rockspec