HipHop on OSX

So, with this pull request (and with the instructions on https://github.com/facebook/hiphop-php/wiki/Building-and-installing-HHVM-on-OSX-10.8) hiphop actually builds and links correctly!

It even runs, but unfortunately dies horribly with:

```
air:hiphop-php goapsychadelic$ ./hphp/hhvm/hhvm --version
HipHop VM v2.1.0-dev (rel)
Compiler: heads/osx-revised-0-g0dc81040394222f60c68ed1f2d8c8781387b6fe1
Repo schema: c7358c211937875791ec36ea0d591a6b9dff12ec
hhvm(16196) malloc: *** error for object 0x11469c570: pointer being freed was not allocated
*** set a breakpoint in malloc_error_break to debug
Abort trap: 6
```

To be honest, I don't really have a clue where to go from here. I could ask you guys to do another review, but I doubt I'd be able to solve these things in a reasonable manner. Hopefully you can have an engineer that actually knows C++ to look at these for a day and if needed implement -proper- solutions?

Especially the gettimeofday looks pretty nasty to me (0dcc26f), but also inotify (4947237) and some of the stuff that that messes with ASM (bbd0d92, 42dd5c9).

Help me out! :)