Setting a protocol handler

[Rex Dieter]

OK, I consulted ktorrent upstream on this, and it seems it gets the 
magnet protocol handling via /usr/share/kde4/services/magnet.protocol 
which is a (imo) deprecated way of doing it (vs. the setting 
MimeTypes=x-scheme-handler/magnet way).

A secondary issue specific to our current ktorrent builds is that we 
still build it with kio_magnet support, which upstream currently does 
not recommend.

So, I'll see if I can sort out the mess, and come up with something that 
works better.

-- rex