Changes to make the root of parentless items = -4 (security context root) instead of 0 (unregistered visitor)
Sites upgradeed from 4.6-4.6.1 have been operating with -4 as the parent_id for years (for example openacs.org) while new installs had
parent_id = 0. This caused problems with the new package_id code that calls content_item__get_root_folder which was assuming the root =
0. It looks like the new install code did not accomodate parent_id=-4 and that is now fixed.
Needs testing on Oracle.