fix uninstall target with configurable rustlib directory
rustdoc: Don't strip empty modules with documentation

Closes #11443
doc: build the docs for librustuv

Closes #11444
rustdoc: Get --version working

Closes #11421
rustdoc: Don't show private modules
librustc: Check restrictions on all subcomponents of a path when moving
it. r=nikomatsakis
Re-implement --help in rustpkg

Fixes #11423
auto merge of #11459 : tedhorst/rust/uninstall_rustlib, r=alexcrichton

Update the uninstall target with the configurable rust lib directory name.

cc @jhasse
auto merge of #11465 : pcwalton/rust/borrow-check-bug, r=pcwalton

it. r=nikomatsakis
auto merge of #11466 : eminence/rust/fix_rustpkg_help, r=brson

It appears --help got lost in aa50ebd03ed1d1f698d0d275f9570ef53e720831

Fixes #11423
rustdoc: Don't show a fields header if there are none
auto merge of #11461 : alexcrichton/rust/rustdoc-fixes, r=brson

See the commits.
rustc: Remove one unnecessary transmute_mut
extra::workcache: Remove unused Logger
rustpkg: Do not guess version if not given

rustpkg accessed git repo to read tags and guess package version,
but it's not quite useful: version can be given explicitly by user,
and implicit guess may cause confusions.
rustpkg::version: Remove enum Version

Replaced by `Option<~str>`.
rustpkg: Compute hash to find crate

Previously rustpkg tried to parse filenames to find crate. Since we now
use deterministic hashes, it becomes possible to directly construct
filename and check if the file exists.
short_name -> name (part of removing CrateId
path: Path -> ~str
CrateId: remove to_str