clean up recent incorrect change in Symtab code that validated the property generation for extension type attributes

--HG--
extra : amend_source : d2906987d10e7770ca09dde406219fb0d6a5d38c

allow signature return type annotations to provide a more specific return object type for def functions

--HG--
extra : amend_source : fe959a1a34b1e190fbe051c7058fcf51c50a2fa8

--HG--
extra : amend_source : 49ba7a5625c69a46f550f471dfbd462a5082b27c

speed up cythonized hexiom2 benchmark a little by using C int arrays instead of fixed size Python lists

--HG--
extra : amend_source : c0a1e78dbfd443585a80bd646b763617eeb6b7c5

allow list literals with a constant multiplier to be assigned to C arrays, extend array assignment tests

This seems to have been a mis-understanding on how C++ works/is wrapped.

prevent recursively generated Cython utility code (i.e. used by other Cython utility code) from appearing multiple times in the output due to a different outer module scope