vbtodrupal 6.x-1.0-rc1

Major release, that should make this module fully usable with Drupal 6! The list of changes are:

• Tested and tweaked to make module work with Drupal 6;
• Rewrote functions that import into Comment Upload and Private Message, vB to Drupal should now work with Drupal 6 versions of these modules;
• #370686: Option to purge or mass delete before importing;
• added delete imported data menu item (available through /admin/build/vbtodrupal/delete_import -- warning: this mass deletes data!);
• improvements to threaded conversation import;