Update section on new `emit <EVENT>` support.
Update section on new `emit <EVENT>` support.

This part of the README must be completely overhauled before the
release, so much of the contents is basically just TODO or design
ideas atm.

Signed-off-by: Joachim Nilsson <583c295fd7602c168ad814279bbc3894ba65f5d6@gmail.com>

troglobit/finit,westermo/finit,troglobit/finit,westermo/finit