Moved .sleep() to Timer.
Add assert_once_ever macro. Close #7748. (fixme cf #8472)
Added home_for_io_with_sched variant. Temporarily making IO unkillable.
Add PointerKind to LpDeref
small cleanups in task/spawn.rs
Prohibit assignment to `&mut` pointers that are found in frozen or borrowed locations.

Fixes #8625.
Don't fail in port.try_recv() the second time. Close #7800.
Only bug on self-not-mapped-to-def if no previous errors were present. Close #6642.
Make json::to_xxx(&Json) fns Json::to_xxx(&self)

to_str, to_pretty_str, to_writer, and to_pretty_writer were at the top
level of extra::json, this moves them into an impl for Json to match
with what's been done for the rest of libextra and libstd.
On Windows, use g++ for linking, instead of gcc.
This is required in order to produce linked modules that perform correct registration of unwind tables.
Un-disable stack unwinding on Windows.
Emit unwind info in rustrt assembly files on Windows.
Compile via external assembler on Windows.
Enabled tests.
Cleanup assembly source.
debuginfo: Big cleanup refactoring and support for foreign_item_fn.
debuginfo: Improved handling of function preludes.
doc: add range iterators in the for loop section
doc: Fix transmute example
Implement size_hint() on RangeInclusive