Do not show ... when plugin prints nothing.

[LanderN]

Hi!

I'm using the "Show Time machine Progress" plugin from getbitbar.com. This plugin shows the status of Time Machine backups when they are in progress. With official Bitbar, the menu item is hidden when there is no backup in progress because it outputs nothing when no backup is in progress, however with your fork, it shows "..." in the menu bar.

Is it possible to not show the item, like the old Bitbar did? Thanks!