ModifyFilterDialog: Prepare for filter editing
ModifyFilterDialog: Correctly set the filter instance
FilterPage: Correctly update the filter list after modiying a filter
Setttings: Remove unused get_bool
Revert "Tweet: Use an array to store the urls"

This reverts commit a4ddaeb18445678920af08338eda2ef64a8d32af.
Tweet: Remove get_urls again