TODO for libirman

. make ir_init_commands read /etc/irman.conf _and_ ~/.irmanrc so that
  bind's can be defined in /etc/irman.conf and alias's defined in ~/.irmanrc
. implement `assign' in irman.conf
. implement variables in irman.conf
. event layer - instead of commands, callbacks.
. redo bind / alias to work more dynamically, so as to enable many codes
  to map to one alias.