Rust 0.2.0

* >1500 changes, numerous bugfixes

* New docs and doc tooling

* New port: FreeBSD x86_64

* Compilation model enhancements

* Generics now specialized, multiply instantiated

* Functions now inlined across separate crates

* Scheduling, stack and threading fixes

* Noticeably improved message-passing performance

* Explicit schedulers

* Callbacks from C

* Helgrind clean

* Experimental new language features

* Operator overloading

* Region pointers

* Classes

* Various language extensions

* C-callback function types: 'crust fn ...'

* Infinite-loop construct: 'loop { ... }'

* Shorten 'mutable' to 'mut'

* Required mutable-local qualifier: 'let mut ...'

Basic glob-exporting: 'export foo::;'

* Alt now exhaustive, 'alt check' for runtime-checked

* Block-function form of 'for' loop, with 'break' and 'ret'.

* New library code

* AST quasi-quote syntax extension

* Revived libuv interface

* New modules: core::{future, iter}, std::arena

Merged per-platform std::{os, fs*} to core::{libc, os}

* Extensive cleanup, regularization in libstd, libcore