LLVM 4.0.0 released

The LLVM 4.0.0 release is out. "This release is the result of the community's work over the past sixmonths, including: use of profile data in ThinLTO, more aggressiveaggressive dead code elimination, experimental support for coroutines,experimental AVR target, better GNU ld compatibility and significantperformance improvements in LLD, as well as improved optimizations,many bug fixes and more." The LLVM compiler project has moved to anew numbering scheme with this release, where the first number incrementswith each major release.