Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

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

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

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 r86140.

Import LLVM r73070.

Now I'm going to stop importing code for a while. I spent a lot of time
the last couple of days figuring out which LLVM commit caused g++ to
miscompile, which in its turn caused Clang to miscompile the next build.
I had to run `make buildworld' twice each time I bisected a revision.

Import LLVM, at r72732.