added a way to mark set/bind/unbind commands as important in ~/.tmux.conf.local, closes #571

inspired by css, any set/bind/unbind command ending with #!important will be
executed honored, e.g.:

bind-key -T copy-mode-vi Escape send-keys -X clear-selection #!important

.tmux.conf.local

@@ -354,6 +354,9 @@ tmux_conf_copy_to_os_clipboard=false
 # set -g prefix C-a
 # bind C-a send-prefix
 
+# if you don't want Oh my tmux! to alter a binding, use #!important
+# bind v new-window -c #{pane_current_path} #!important
+
 # move status line to top
 #set -g status-position top