Merge remote-tracking branch 'mozilla/master'

Conflicts:
	src/libextra/test.rs
	src/libstd/at_vec.rs
	src/libstd/cleanup.rs
	src/libstd/rt/comm.rs
	src/libstd/rt/global_heap.rs
	src/libstd/task/spawn.rs
	src/libstd/unstable/lang.rs
	src/libstd/vec.rs
	src/rt/rustrt.def.in
	src/test/run-pass/extern-pub.rs