wine.inf: Add shell handler for .url files.

[Hans Leidekker]

On Fri, 2011-04-08 at 09:35 +0200, Damjan Jovanovic wrote:

> Aren't most Internet-related file associations created by
> dlls/mshtml/mshtml.inf instead of tools/wine.inf.in, and should we
> maybe change that or move your patch there?

Looks like InternetShortcut is registered both by shdocvw and mshtml.
I'm not sure about moving this stuff there, winebrowser should perhaps
always be available as a fallback, even if our builtin browser is
unregistered.