Fix unwinding on OS X 10.9.

OS X 10.9's linker has a bug that results in it failing to preserve
DWARF unwind information when passed the -no_compact_unwind flag.
This flag is passed on OS X because the unwind information for
__morestack cannot be represented by the compact unwind format.

We can work around this problem by using a more targeted approach
to disabling compact unwind information. The OS X linker looks for
a particular pattern in the DWARF unwind information and will not
attempt to convert the unwind information to the compact format.
The pattern in question is the return address register being saved
twice to the same location.

Fixes #6849.
Drop the '2' suffix from logging macros

Who doesn't like a massive renaming?
Remove the now-duplicate logging macros
Remove old logging from the tutorial
auto merge of #10006 : alexcrichton/rust/another-massive-rename, r=brson

Drop the `2` suffix on all of them, updating all code in the process of doing so. This is a completely automated change, and it's dependent on the snapshots going through.
add feature gate for managed boxes

I'll flip this on after doing a snapshot. This syntax may or may not
stay around, and managed boxes are currently not very useful. They have
the same overall performance characteristics as `std::rc::Rc`, but are
significantly slower, allocate larger boxes and hold onto the memory
beyond when it is needed due to lacking move semantics.

There are currently two useful aspects of the type:

* the dereference sugar, which we should implement for `Rc`
* the annihilator freeing cycles at the end of the task
Minor grammatical fixes and removed section on 'rust' tool
auto merge of #9923 : thestinger/rust/managed_boxes, r=brson

I'll flip this on after doing a snapshot. This syntax may or may not
stay around, and managed boxes are currently not very useful. They have
the same overall performance characteristics as `std::rc::Rc`, but are
significantly slower, allocate larger boxes and hold onto the memory
beyond when it is needed due to lacking move semantics.

There are currently two useful aspects of the type:

* the dereference sugar, which we should implement for `Rc`
* the annihilator freeing cycles at the end of the task
Don't Make str field private
Making fields in std and extra : private  #4386
Removed Unnecessary comments and white spaces  #4386
Removed unnecessary comments and white spaces as suggested
Removed the unnecesary comments
Removed the file src/libstd/unstable/extfmt.r
auto merge of #10013 : bdash/rust/mavericks-unwinding, r=alexcrichton

OS X 10.9's linker has a bug that results in it failing to preserve
DWARF unwind information when passed the -no_compact_unwind flag.
This flag is passed on OS X because the unwind information for
__morestack cannot be represented by the compact unwind format.

We can work around this problem by using a more targeted approach
to disabling compact unwind information. The OS X linker looks for
a particular pattern in the DWARF unwind information and will not
attempt to convert the unwind information to the compact format.
The pattern in question is the return address register being saved
twice to the same location.

Fixes #6849.
Making ai_next field public
auto merge of #9969 : reedlepee123/rust/priv_fields, r=bstrie
Tidy up asm! usage in libstd
std::rand: add the Sample and IndependentSample traits.

These are a "parameterised" Rand.
std::rand: Add RandSample for Sample-ing Rand types directly.