Deprecate these two ports. libtorrent-rasterbar version 0.13 is very old,
and no longer considered the most up to date version. sharktorrent is the
only port left that depends on it, and the version in ports is very old.
With alepulver's permission assume maintainership of sharktorrent for the
purpsoe of shepherding the deprecation. If anyone wants to update it to
a more modern version that depends on libtorrent-rasterbar version 0.14.8
or newer, feel free.