Fix vsplit BlackBox

thanks to Иван Алёхин
Generate BlackBox funInputs dataCons in a HO-function position
Correctly generate all VHDL types
Remove BlackBox for vzip and vunzip.

There are now specified in terms of other functions for which
BlackBoxes exist.
Add test for DataCons in HO-function position

Where the HO-function is a primitive, e.g. vmap Just
Add test for vzip and vunzip now that they are no longer primitive
Add test for vsplit