[PATCH] [libcxx] Add EXCLUDES tag to lit. It mirrors REQUIRES.

[Eric Fiselier]

Thanks for looking at this Dan.

A lot of our tests replace operator new and operator delete. MSAN and ASAN also replace operator new/delete. This causes a linking error. Theres nothing wrong with the tests other than they just can't be run with MSAN or ASAN. I think these should be considered unsupported as opposed to expected failures.

I hope that clarifies things.

http://reviews.llvm.org/D4950