ctorrent: new package

Closes #243.

CTorrent is a BitTorrent client implemented in C++
to be lightweight and quick.
This is the enhanced version from
http://www.rahul.net/dholmes/ctorrent/



[Peter: minor kconfig tweaks]

Signed-off-by: Olaf Rempel <razzor@kopf-tisch.de>
Tested-by: Will Newton <will.newton@gmail.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>