OS X Installer

[Walter Bright]

Michel Fortin wrote:
> If I'm not mistaken, both your D1 and D2 installer install at the same 
> location and they will overwrite each other. I'd much prefer if D2 and 
> D1 could coexist without having to go with a special installer or custom 
> installation instructions. Otherwise it'll be hard for me to offer the 
> choice between D1 and D2 in Xcode (and I certainly do want that choice 
> to be available).
> 
> Thoughts?

I've been switching the directories to {dmd, dmd2} so they can coexist.