tmux: Make window-navigation bindings repeatable

This way the prefix only has to be pressed once. (As long as the key is
repeated in `repeat-time`)

.config/tmux/tmux.conf

@@ -38,6 +38,12 @@ set -g renumber-windows on
 # of the prefix. (Exists already per default with prefix)
 bind-key -n PPage copy-mode -u
 
+# Repeatable window-navigation bindings
+bind-key -r -T prefix   n next-window
+bind-key -r -T prefix C-n next-window
+bind-key -r -T prefix   p previous-window
+bind-key -r -T prefix C-p previous-window
+
 # Vim-bindings
 
 # Enter copy-mode with Escape