[tmux] Try `mode-mouse` on
[emacs] `xterm-mouse-mode` on
Ignore `ac-comphist.dat`

Files record user data for auto-complete-mode.
@see http://cx4a.org/software/auto-complete/manual.ja.html#.E8.A3.9C.E5.AE.8C.E6.8E.A8.E6.B8.AC.E6.A9.9F.E8.83.BD