testing/libtorrent-rasterbar: upgrade to 1.2.14

Patchset from Wolf wolf@wolfsden.cz via aports #3550:

Since tests do not seem to hang any longer, there we re-enabled.

Due to changes in upstream's build of python binding, just copied over
python extension was not picked up by the interpret, so they are now
installed using setup.py instead of relying on make install.