apple-gcc42 is now in homebrew/dupes

I was getting this error:
```
brew install apple-gcc42
Error: No available formula for apple-gcc42 
Searching taps...
homebrew/dupes/apple-gcc42
```
Indeed, you need to `brew tap homebrew/dupes`  for `install apple-gcc42` to work, and **I'm assuming `homebrew/versions` is where apple-gcc42 was before.**

Apologies about github adding a newline at the end of the file, I'm sure homebrew won't choke on this