* app/pdb/gimppdb-utils.[ch]: add "gboolean writable" parameter to
  gimp_pdb_item_is_attached() because this function is called on
  almost all items where a check for locked is needed.

* tools/pdbgen/pdb/*.pdb: pass writable = TRUE in all checks for items
  that are modified. Add explicit calls to gimp_pdb_item_is_writable()
  in some rare cases.

* app/pdb/*-cmds.c: regenerated.