Silence some unused import warnings
Correctly reset steals when hitting MAX_STEALS

The previous code erroneously assumed that 'steals > cnt' was always true, but
that was a false assumption. The code was altered to decrement steals to a
minimum of 0 instead of taking all of cnt into account.

I didn't include the exact test from #12295 because it could run for quite
awhile, and instead set the threshold for MAX_STEALS to much lower during
testing. I found that this triggered the old bug quite frequently when running
without this fix.

Closes #12295
auto merge of #12302 : alexcrichton/rust/issue-12295, r=brson

The previous code erroneously assumed that 'steals > cnt' was always true, but
that was a false assumption. The code was altered to decrement steals to a
minimum of 0 instead of taking all of cnt into account.

I didn't include the exact test from #12295 because it could run for quite
awhile, and instead set the threshold for MAX_STEALS to much lower during
testing. I found that this triggered the old bug quite frequently when running
without this fix.

Closes #12295
Implement Show for 1-12 element tuples
Delegate ToStr implementation to Show for tuples
auto merge of #12310 : brson/rust/mkfilecleanup, r=sfackler

Two small fixes
Merge ImmutableTuple* traits into their respective Tuple* trait
Ignore /build even if it’s a symlink.
Improve naming of tuple getters, and add mutable tuple getter

Renames the `n*` and `n*_ref` tuple getters to `val*` and `ref*` respectively, and adds `mut*` getters.
Remove CloneableTuple and ImmutableTuple traits

These are adequately covered by the Tuple2 trait.
auto merge of #12313 : bjz/rust/tuple, r=huonw

This renames the `n*` and `n*_ref` tuple getters to `val*` and `ref*` respectively, and adds `mut*` getters. It also removes the `CloneableTuple` and `ImmutableTuple` traits.
auto merge of #12312 : brson/rust/doc, r=alexcrichton

Only single out std. Put everything else in a consistent list.
auto merge of #12319 : SimonSapin/rust/build-symlink, r=alexcrichton
Allow configuration of uid/gid/detach on processes

This just copies the libuv implementation for libnative which seems reasonable
enough (uid/gid fail on windows).

Closes #12082
Upgrade libuv

This notably includes joyent/libuv@6f62d62c in order to fix when processes fail
to spawn on windows
auto merge of #12085 : alexcrichton/rust/issue-12082, r=brson

This just copies the libuv implementation for libnative which seems reasonable
enough (uid/gid fail on windows).

Closes #12082
std: Move intrinsics to std::intrinsics.

Issue #1457
std: Move raw to std::raw

Issue #1457