Clear to the end of the screen from the right starting point when drawing
line-by-line (in panes or if ed not supported). Fixes problem spotted by Frank
Terbeck.
Switch the tty key tree over to an (unbalanced) ternary tree which allows
partial matches to be done (they wait for further data or a timer to expire,
like a naked escape).
Mouse and xterm-style keys still expect to be atomic.
key_string_lookup_key uses a static buffer, so copy its output into the working
buffer before calling the command print function which can also use it (eg
send-keys).
Switch tty key input over to happen on a read event. This is a bit more
complicated because of escape input, but in that case instead of processing a
key immediately, schedule a timer and reprocess the bufer when it expires.
This currently assumes that keys will be atomic (ie that if eg F1 is pressed
the entire sequence is present in the buffer). This is usually but not always
true, a change in the tree format so it can differentiate potential (partial)
key sequences will happens soon and will allow this to be fixed.
Convert the window pane (pty master side) fd over to use a bufferevent.
The evbuffer API is very similar to the existing tmux buffer API so this was
remarkably painless. Not many possible ways to do it, I suppose.
Initial changes to move tmux to libevent.
This moves the client-side loops are pretty much fully over to event-based only
(tmux.c and client.c) but server-side (server.c and friends) treats libevent as
a sort of clever poll, waking up after every event to run various things.
Moving the server stuff over to bufferevents and timers and so on will come
later.
Add an activity time for clients, like for sessions, and change session and
client lookup to pick the most recently used rather than the most recently
created - this is much more useful when used interactively and (because the
activity time is set at creation) should have no effect on source-file.
Based on a problem reported by Jan Johansson.
If it isn't available explicitly, work out the current client in a similar way
to the current session - build a list of the possibilities then pick the
newest.
Change session and client activity and creation time members to have more
meaningful names.
Also, remove the code to try and update the session activity time for the
command client when a command message is received as is pointless because it
des not have a session.
