mozilla/servo — pull request #568 by SimonSapin (2013-07-10 16:06:32+00:00)
Title: Add a submodule for rust-cssparser

[As discussed](https://github.com/mozilla/servo/wiki/Meeting-2013-07-01#css), even though this parser is not used yet, having it built and tested with the rest of Servo helps ensure it does not bitrot.