adding travis support

This is all that's needed to enable Travis, but since I'm not the repository owner I can't set it up completely. 
It's really simple, you connect your github here: https://travis-ci.org/ , the getting started guide is here: http://docs.travis-ci.com/user/getting-started/ . 

All you really need to do after signing in is go here https://travis-ci.org/profile , flick the switch for the HearthSim project. Next push that happens, the build should trigger, and we'll have CI!