* add CacheCookieMixin to ERP5Site and use its methods
  instead of manually using ZODBCookie's
* rename resetDynamicDocuments to synchronizeDynamicModules
  to clarify its role.
* use "force" instead of "slave" and document the meaning
  more clearly
* put all cookie-related code inside synchronizeDynamicModules


git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@38666 20353a03-c40f-0410-a6d1-a30d3c3de9de