Move FileSystemListener from custom/ to midp/
Move FileSystemRegistry from custom/ to midp/
Allow classes in cldc1.1.1/, vm/ and midp/ to use classes in custom/
Implement FileSystemRegistry::getRootsImpl native
Move some JSR-75 RI classes from midp/ to jsr-075-ri/
Merge pull request #621 from marco-c/remove_file_classes_from_custom

Move FileSystemListener from custom/ to midp/