for now default DB_SESSION to false

for now default DB_SESSION to false
PagePerm:
  * not existing perms will now query the parent, and not
    return the default perm
  * added pagePermissions func which returns the object per page
  * added getAccessDescription
WikiUserNew:
  * added global ->prepare (not yet used) with smart user/pref/member table prefixing.
  * force init of authdbh in the 2 db classes
main:
  * fixed session handling (not triple auth request anymore)
  * don't store cookie prefs with sessions
stdlib: global obj2hash helper from _AuthInfo, also needed for PagePerm

git-svn-id: svn://svn.code.sf.net/p/phpwiki/code/trunk@2988 96ab9672-09ca-45d6-a79d-3d69d39ca109