Don't reject unknown remote commands

Daemon plugins can implement them.
Alias F5/^r to refresh

Seems like that's what everyone expects them to do anyway...
Don't crash on die() if window is already dead

Resizes and other mundane stuff can cause a window to be killed and
refreshed, so if a die() is called from a command and the window isn't
being tracked by the Screen, just forget about it.
Fix empty completions
Add :reset-config command to reset canto-curses settings
Remove dead keybinds
Don't print blank remote output