[S02] Get rid of Polymorphic Types
[S02] Get rid of Polymorphic Types

The idea was novel, but sadly it introduces a terrible set of
consequences. Additionally, no-one ever implemented it, and it's never
been really necessary.

Also, the pipe character was already in use in other ways. That's just
untenable.

prammer/specs,perl6/specs,prammer/specs,prammer/specs,tokuhirom/specs,tokuhirom/specs,perl6/specs,tokuhirom/specs