Where should cabal install to by default?

[Isaac Dupree]

Duncan Coutts wrote:
> ...
> For unix systems, do per-user installs to --prefix=~/.cabal but if ~/bin
> exists then add symlinks there.

just a reminder for anyone: if a directory is not already in 
$PATH then it's annoying to change $PATH; older shell 
sessions won't be updated automatically with the new $PATH, 
at least.  Makes it a little harder to give the user advice 
on what to do, in the cases in which we have to resort to 
merely giving advice.

-Isaac