Add clone support for cloning one factories definition stack into another

Now supports the __factory() accessor
Cloned factories will switch accessor
Check BackboneFactory to see how this can be used
This arose from a need to clone the definitions of a factory
and have the definicitions in that factory be available to instances
regardless of cloning.
Fixed bug in clone support

lazy initialization of tagCbs and tagMap arrays in case cloning is done.
Merge pull request #4 from webspinner/master

Add clone support for cloning one factories definition stack into another