This covers the "stateDial" handler, which processes issuing a new dial
request in the middle of a call, but on the same call leg. This was
something commonly used in Bayonne1 because there was no explicit "sieze
and connect to destination" option when initially creating a call leg.
Hence, in Bayonne1 you would seize, start a new call leg, and then that
script would dial the destination number separately from a dial command
by going into a "dial" state.
enterDial/stateDial is mostly leftover for legacy compatibility when
migrating drivers (and scripts) that need to behave the same as in
Bayonne1, and may still be potentially useful when doing call lists
under script control as well.