keymap.lisp: move push-input-event into own function
keymap.lisp: move push-input-event into own function

so that we can reproduce it on the repl.

(%%push-input-event 65 "a" '("") 0.0 0.0 65 "1")
(%%push-input-event 22 "BACKSPACE" '("") 0.0 0.0 65288 "1")

jmercouris/NeXT,jmercouris/NeXT