Shift-Option-I now selects the next actor and edits initiative

~~resolve #4  in SHA 005adf6~~
resolve #3  in SHA fb0973a
resolve #6  in SHA c9d138a
resolve #5  in SHA c9d138a
resolve #4 in SHA b9e4963a99f881fc94eddbf74bc27b33b01cb5be
`_.find` returns `undefined` if no match, so we'd have to harden `Actors.setSelected()` to ensure that it doesn't explose on receiving [my favorite Javascript value ever]