Gravity Flow Folders 1.8

- Fixed an issue with the RTL Languages not displaying folders correctly in Workflow Folder Settings.

- Added security enhancements.
- Added filter gravityflowfolders_folder_match_add_step to allow control of whether entry should be added to a folder
- Added filter gravityflowfolders_folder_match_remove_step to allow control of whether entry should be removed from a folder
- Added filter gravityflowfolders_display_folder to allow the folder shortcode argument to be customized.
- Updated translations.

Added support for the license key constant GRAVITY_FLOW_FOLDERS_LICENSE_KEY.