Only display start, pause, stop, home buttons when applicable

[trancefam]

• when vacuum is running, hide start button
• when vacuum is paused or idle, hide pause and stop buttons
• when vacuum is returning to dock, hide home and stop buttons
• when vacuum is docked, hide pause, stop, and home buttons

[TheLastProject]

Wow, this is such an improvement in such relatively little code I can't believe I never bothered to implement this myself. Thanks!