The type for the self argument for binops depends on the compile
directives. Therefore it needs a set of type slots that depends
on the compiler directives.

I've therefore got rid of the big static list of typeslots in
TypeSlots.py in favour of a class that defines them all (and
can be initialized with suitable compiler directives as needed).
This involves moving a static dictionary and list out of the
global scope too, so that they too can be part of the class.
The passing of the dictionary and list to all the constructors
is a bit awkward

Fixes https://github.com/cython/cython/issues/4434