Remember height of find in folder results
Add Select None to file browser’s action menu

This makes it easier for the user to discover that ⇧⌘A can be used to deselect all (useful e.g. prior to running a SCM command).
Remove Edit → Select → None

This can now instead be found in the file browser’s action menu, as it (by design) only works on the file browser, not the text view.

Closes #883.