I overlooked the fact that the ffmpeg/libav build system only supports `--cc`
and completly ignores $CC. Hopefully this makes the build times a little
faster.
Fixes#332
Travis-CI [1] is a continous integration cloud service. It is free for
open-source projects and tigthly integrated tiwh GitHub so there is really
no reason for us not use it. :)
For now we are going to do a total of 4 builds, mainly to test ffmpeg/libav
API breakage:
* ffmpeg-stable, libass-stable
* ffmpeg-git, libass-stable
* libav-stable, libass-stable
* libav-git, libass-stable
The compiler that is currently used is clang for two reasons:
* running 8 build targets would be quite wasteful and take a long time
* clang is less tested and used during development than gcc (especially on
linux)
Currently Travis doesn't support OS X environments alongside Linux ones [2].
When it will, we will add a fifth build target to test OS X compilation
breakage.
README was moved to markdown to add the little build status image. I ran some
tests with my GitHub fork and couldn't get images to show up using ReStructured
Text.
[1]: https://github.com/travis-ci/travis-ci
[2]: travis-ci/travis-ci#216
