Revert "Removed unused input in ZX90_CR pulse"
Revert "Removed unused input in ZX90_CR pulse"

This reverts commit ef3b8b5946645447557a1f585be9e7af6f09b1cd.

rmcgurrin/PyQLab,calebjordan/PyQLab,BBN-Q/PyQLab,Plourde-Research-Lab/PyQLab