To install the pluggin, just type "make install". It will install itself
and tell you where it expects to find the players. You can change this
by editing the makefile and recompiling.

Then you need to put some players in that directory. You can start by
trying out the players in the Examples directory (don't forget to
deactivate any native input plugin that would handle the files you want
to play with the meta-input player).
