[physfs] physfs fails if $HOME does not exist

[Ryan C. Gordon]

> could you please have a look at 
> http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=553174

These two patches should fix it...
    http://hg.icculus.org/icculus/physfs/rev/6d3a91a5029b
    http://hg.icculus.org/icculus/physfs/rev/b45193ab2033

And here's a single patch, backported to stable-2.0...
    http://hg.icculus.org/icculus/physfs/raw-rev/5ad7902d1ab9

This will go in the 2.0.1 release once I clean up some last issues.

--ryan.