No respecting core fields weights with fieldgroup tab formatters

If you select the option to show all the residual fields in a tab, the ones that are not part of any fieldgroup tab, then when showing the node, you get that core fields and cck fields are not ordered as you have set up for that content type, (in fact only cck fields are ordered but without the core fields).

This patch moves the rest of fields (#content_extra_fields) that haven't been moved into the residual tab (originally only cck fields), and also set the #pre_render of this extra_fields in order to allow that tabs rendered them correctly.

With this patch is possible to show any node with a full tab layout, in the same way and order that you get when no using any tab.