Access filter - FileFilter broken

Discovered thanks to testing by @RN

Basically the change in logic to only reload the file containing the b32s if it has changed broke the filter. The b32s are blocked only during the first SYNC_INTERVAL; the next sync removes them from the filter.

Solution is to "remember" the last set of b32s that were loaded in the FileFilterDefinitionElement and then if the file's lastModifiedTime has not changed return those in the update method.