sorry, I'd like to bump LLVM again, the previous version happened to be
incapable of building LLVM even without Souper due to crashing on quite
a few files.  this one builds itself just fine.
don't tell people the default is on/off since the cl::opt class doesn't accept
those strings, use true/false instead
Merge pull request #77 from regehr/cleanup

cmd line help cleanup
Merge pull request #76 from regehr/bump-llvm

sorry, I'd like to bump LLVM again, the previous version happened to be