merge the formerly debian-specific x-terminal-emulator patch

I think instead of maintaining distribution-specific patches forever,
it’s a bit easier to have them applied upstream, especially since they
don’t break anything.

fixes #876
bugfix: copy binding before run

Copy the binding struct before running it and use this copy to emit the
binding event.

This fixes a crash when the command `reload` is used in a binding when
the binding event is emitted.