ProgrammingRightCheckerListener is not actualy doing what it's supposed to

ProgrammingRightCheckerListener is using dropPermissions() which cause two important problems:

• dropPermissions() actually covers way more than PR right now for all the script classes extending com.xpn.xwiki.api.Document (for example impossible to use Document#saveAsAuthor with it)
• dropPermissions() is not really part of the security module, so it's not taken into account at all when you directly use AuthorizationManager