github triple backtick code support

[trvsdnn]

Github Markdown can use triple backticks to start and end a code section, this is useful because it's the only way to specify a language for syntax highlighting.

Would it be appropriate to include this in the markdown bundle (given it's github flavored markdown)?

As of now README files look a a little sad if you're using the triple backtick syntax.

[infininight]

There are many variants of markdown out there, so what would need to happen is a separate grammar be created that augments the markdown grammar, probably in a Github bundle.

[sorbits]

See issue #15 for how this can be added (without touching the base Markdown grammar).

[MikeMcQuaid]

TextMate 2 now has a Markdown (GitHub) bundle under "Bundles" that I think may address many of the folks' desires here (repository for the curious: https://github.com/MikeMcQuaid/GitHub-Markdown.tmbundle).