tmux: Cycle windows with Alt-Page{Up,Down}

Also change the only other use of PPage (i.e. PageUp) to PgUp. PageUp
and PageDown would probably be nicest, but I like that PgUp and PgDn are
of equal length. I dislike NPage and PPage.

.config/tmux/tmux.conf

@@ -145,7 +145,7 @@ set -g pane-base-index 1
 
 # Enter copy-mode and scroll one page up directly with PageUp without the need
 # of the prefix. (Exists already per default with prefix)
-bind -n PPage copy-mode -u
+bind -n PgUp copy-mode -u
 
 # Repeatable window-navigation bindings
 bind -r   n next
@@ -153,6 +153,10 @@ bind -r C-n next
 bind -r   p prev
 bind -r C-p prev
 
+# Change windows with Alt-Page{Up,Down} analog to Ctrl-Page{Up,Down} in vim
+bind -n M-PgUp prev
+bind -n M-PgDn next
+
 # Jump back to last focused window
 bind C-o last-window