ZODB Components: Allow migration of {Interface,Mixin,Module,Tool} from Business Template UI and on all Products (not only Products.ERP5).

This introduces the following new ZODB Components:
  + Module Component: Non-Documents/non-persistent classes of modules usually
    found at the top-level of Products (eg Products.ERP5.XXX) on FS. Considering
    that all other Components types are actually Modules, make it the base class.
  + Tool Component: Tool directory of Products on FS (eg Products.ERP5.Tool.XXX).
    => DiffTool and CallableTool are now 'Tool Component' instead of plain
       'Document Component' and properly registered as Tools like FS Products Tool.

Skip CMFActivity and HBTreeFolder2 Products for now in migration View for now as
almost many Portal Type classes have ActiveObject or HBTreeFolder2 in their MRO
and these Products will be done at the end anyway...