[Developers] Patch so SSHKeyChain will load V1 keys

[Aaron Jacobs]

> However a co-worker of mine who knows more about such things than me
> (Thanks, Larry!) said that NSASCIIStringEncoding was actually less  
> fussy
> about random data than UTF-8 and this made for a shorter patch, so I
> liked it better :) It's unclear exactly what NSString does with those
> high-ascii values, however it is very clear that we are only  
> interested
> in the first line which contains valid 7-bit ascii and that the fixed
> version will load my v1 keys while the head revision would not.

Okay.  But it should be noted that it was fixed only by a _side  
effect_ (undocumented?) of changing it to NSASCIIStringEncoding.   
Anything that is valid ASCII is also valid UTF-8, so there's  
definitely something there that is not valid ASCII, as you said.   
Perhaps a more correct solution like your first thought would be better.

Aaron