Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Upgrade our copy of llvm/clang to r168974, from upstream's release_32
branch. This is effectively llvm/clang 3.2 RC2; the 3.2 release is
coming soon.

Upgrade our copy of llvm/clang to r142614, from upstream's release_30
branch. This brings us very close to the 3.0 release, which is expected
in a week or two.

MFC after: 1 week

Import LLVM/clang from vendor stripped of docs/ test/ website/ www/ examples/
in llvm/ and/or llvm/contrib/clang/ respectively.

Approved by: ed (mentor)
Approved by: core

Update LLVM to 92395.

Update LLVM to r86140.

Update llvm to r84119.

Import LLVM, at r72732.