[FEATURE REQUEST] Support blacklisting applications

[albertsj1]

First, thanks for the software. It's pretty cool to easily see what apps I use throughout the day.

It would be nice if there was a way to blacklist an application so it doesn't show in the output at all. One example use case for me is with 'Path Finder'. I use it as a desktop replacement for Finder, so Thyme shows it as active 100% of the time.