Base on work by Mame Coumba Sall <mame@nexedi.com>

Allow to control current logged in user credentials through erp5_credentials bt5 (consistent with long implemented "I forgot my password" anonymous login_form).

Add a dummy activity so alarm calling can detect we still have a pending activity and do not start this script again before previous call is finished.

Clean up only "Invoice" specific properties and call "parent" generic script that will adjust causality workflow state as well.

Revert c9448903 (Delivery_afterClone will update  causality state after cloning).

real security configuration should still remain in sub module (modify 4610f372 a bit).

ref. http://comments.gmane.org/gmane.comp.web.zope.cvs/22117

ref. http://comments.gmane.org/gmane.comp.web.zope.cvs/22117

fix class tool's dtml files so that it works on Zope-2.12.23 too. also add some assertions to check if it works.

Revert "define __getitem__ instead of _getOb in class tool so that it works on Zope-2.12.23 too." that broke some tests.

This reverts commit 8670f40a.

Data can be really complex string, which can be bad for tag.

Use volatile cache to store tokens and one key per site.