drop is_not_empty from TreeSet/TreeMap

migrate LinearMap<T, ()> to LinearSet<T>

I'll file an issue.

Translate const references to extern functions as *i8 instead of the typical closure pair. Fixes #4522.

Range checking and miscellaneous fixes tin time library

This eliminates an ICE in trans where the scope for a particular
borrow was a statement ID, but the code in trans that does cleanups
wasn't finding the block with that scope. As per #3860

preserve looks at a node ID to see if it's for a statement -- if it
is, it uses the enclosing scope instead when updating the map that
trans looks at later.

I added a comment noting that this is not the best fix (since it may
cause boxes to be frozen for longer than necessary) and referring
to #3511.

r=nmatsakis

Add more constructors for managed vectors (as proposed in issue #4553)

...now without a random libuv change.

I made a mistake and included some submodule weirdness.
About to re-push the patch without that.

This reverts commit 17ea5482.

Too small to review.

Make the closure take two arguments instead of a single `path_entry`
struct; remove the `path_entry` type. This eliminates a bad copy.

more work on container traits

Add Timespec comment and assert about negative nsec

Eliminates some bad copies.

doc: fix log level ids