Unix path name encoding fix

 
Hi Ian,

when adding the sqGetFilenameFromString() function a year ago we lost  
the character encoding translation that used to happen (and still  
happens in other places in the VM). Attached is a patch for that.

Also, for all, I attached a changeset that actually uses either  
MacRoman or Latin1 to communicate with the VM, before there was a mix  
of both which couldn't actually work. Now I can type characters, copy/
paste text, list directories and read/write files :) This will work  
correctly only with an old (3.7-7) or brand new VM with my patch  
applied.

Göran tested this successfully with a file named "å" (see http://
ircbrowse.com/channel/squeak/20070316).

- Bert -