Support ignoring paths

[isair]

Ability to add paths that will be ignored would be a great feature. I realized that I needed it when using Transmit to edit files on a server. As Transmit first downloads the file to a cache directory, my recently opened directories were flooded with directories containing randomly generated unique names. So in my case I'd add "~/Library/Caches/Cleanup At Startup/Transmit" to ignored paths if I could.