Store name of "suggested" meta{class,role} in the package

[stevan]

We should do our best to make it easy for a user to say "$this package should use $this metaclass", simplest case is to store the appropriate one (mop::role if no @ISA and mop::class if @ISA) in the stash and provide a util method to access it (and maybe construct it for you, who knows).

So sayeth the Rik!!!!

[stevan]

This is blocked by #3