Adding a .travis.yml file to use the travis-ci.org

From wikipedia:

Travis CI is a hosted, distributed continuous integration service used
to build and test projects hosted at GitHub.

Travis CI is configured by adding a file named .travis.yml, which is a
YAML format text file, to the root directory of the GitHub repository.

Travis CI automatically detects when a commit has been made and pushed
to a GitHub repository that is using Travis CI, and each time this
happens, it will try to build the project and run tests. This includes
commits to all branches, not just to the master branch. When that
process has completed, it will notify a developer in the way it has been
configured to do so — for example, by sending an email containing the
test results (showing success or failure), or by posting a message on an
IRC channel. It can be configured to run the tests on a range of
different machines, with different software installed (such as older
versions of a programming language, to test for compatibility).
Merge pull request #190 from sieben/travis-ci

Adding a .travis.yml file to use the travis-ci.org
add libglew-dev to list of packages to get
will hopefully shut up "configure: error: "No usable version of GLEW found."" msg
add compile status from travis-ci; thanks @shakesoda
we don't have a "make test", so travis reports the build as "failed"
(also throw in an IRC notification)
Disabled AddATIToList on Windows because it makes mapconv crash.
maintain music rate speed adjust after music has finished

Keeps things like BGA effect clocks consistent when music stops.
Merge pull request #251 from sigatrev/MusicSpeed

maintain music rate speed adjust after music has finished
added GetStylesForGame method
Merge branch 'GetStylesForGame' of https://github.com/sigatrev/stepmania
Changed GetStylesForGame to not traverse the list of styles twice.
Pretend I didn't forget the +1.
Changed RollingNumbers to not set NAN velocity.
Updated actordef.txt.
fix REALLY BAD TYPO in GradeDisplay:SetGrade Lua function.
this is dumb and I'm too lazy to find out who's REALLY to blame so I want to assume it's my fault, probably. If anyone wants to bother clearing my name, check the stepmania SVN history. I don't care enough :v