Rewrite the 'short summary of features' on rust-lang.org

[brson]

This feature list was written long, long ago. The language is even more awesome than the bullets would suggest. Smaller would be better too. Bonus points for being categorized by the three pillars: safe, concurrent, fast.

Links to appropriate documentation could also be useful.

[brson]

https://github.com/graydon/rust-www/tree/gh-pages

[BrendanEich]

Just noticed the lower-case "turing-" in "turing-complete"...

/be

[lkuper]

+1. And that lower-case "t" has been bothering me for a long time! :)

[bblum]

I was just about to file an issue for some nits I wanted to pick.

"no races or sharing" should be "no data races or sharing", or perhaps just "no shared mutable state"

"garbage collection... only "shared" types" should be "only "managed" types", perhaps

[brson]

I could have sworn I wrote 'more awesomer' in the OP, very much on purpose. Somebody mutilated my grammar!

[brson]

I've updated the list to be more concise. I did drop the mention of supported platforms.

[brson]

Calling this done.