Commit Briefs
bind <up> and <down> for completion instead of history
<up> and <down> are now bound to previous/next-completion instead of previous/next-history-item
support completions in minibuffer + related interactive fns
* cmd.c (cmd_previous_completion): add previous-completion (cmd_next_completion): add next-completion (cmd_insert_current_candidate): add insert-current-candidate * minibuffer.c (enter_minibuffer): support completions in minibuffer