Fixes for changes in cython v0.22.1
Fixes for changes in cython v0.22.1

SymbiFlow/pycapnp,rcrowder/pycapnp,jparyani/pycapnp,tempbottle/pycapnp,jparyani/pycapnp,jparyani/pycapnp,SymbiFlow/pycapnp,tempbottle/pycapnp,SymbiFlow/pycapnp,rcrowder/pycapnp,rcrowder/pycapnp,SymbiFlow/pycapnp,tempbottle/pycapnp,rcrowder/pycapnp,jparyani/pycapnp,tempbottle/pycapnp