Ignore non-privmsg commands to services.

This avoids "No such nick" responses to +draft/typing TAGMSG, etc.

add changelog for v2.1.0-rc1

change the default self-signed certificate filenames

fix TAGMSG playback

1. TAGMSG were incorrectly being considered multilines, because
   Is512() was checking the wrong thing
2. Playback of TAGMSG should depend on event-playback, not on message-tags

/ns erase should confirm with /ns erase rather than unregister.

tweak version strings again

clean up account-notify logout notification

don't need to send account-notify * (logout notification)
because either we never sent the initial account-notify
(if we are being logged out as part of fixupNickEqualsAccount)
or else we are immediately going to kill the client
(if we are being logged out as part of unregister/erase)

include conventional.yaml in releases

fix #1031

last round of feature changes

fix #1030

correct old proxiedConn name

make it clearer when rehash has completed

two cleanups

This avoids conditions where two sessions can be attached to the same client
while not logged into an account.

include account-notify in the response batch

fix plan9 support

fix #1020

fix #1021

fix #1019