[Location Bar] Add the ability to show hidden folders in the subdirectories popup
This MR adds the ability to show hidden folders in the subdirectories popup (when the "Show hidden files" option is enabled), as well as the order in which they are shown (depending on whether the "Show hidden files last" option is enabled or not). The subdirectories popup appears when the user clicks the arrow to the right of the button that represents a path of the URL.
requires frameworks/kio!566 (merged)