title: Tmux change scroll up/down keys
body: <p>Currently when I want to go into scroll mode I press <code>Ctrl+b</code> and then <code>[</code>. However after entering copy-mode, I must use the up and down keys to scroll up or down. I would prefer to <code>k</code> for up and <code>j</code> for down. </p>
  
  <p>How do I change the scrolling behaviour so that scroll down happens when I press <code>k</code> and scroll up happens when I press <code>j</code>?</p>