RayVR

https://github.com/enthought/pyql/commit/27e9d9bf2427f161d4b34d7c8b0a32932bbd2b8d withNominal is not in quantlib < 1.13

It looks like currency.pyx uses `__eq__` method, which was introduced in cython 0.27. The docs state the minimum required version for cython is 0.24.1. If a later version of cython...