IB generated constraints shouldn't even touch StackView-managed views
IB generated constraints shouldn't even touch StackView-managed views

IB-generated constraints can sneak in by various means and must be stopped at the addConstraint level. For views we have no control over, be extra zealous and remove them at updateConstraints time (which should happen immediately before the layout pass).

Also address issues brought up by @CosynPa

CosynPa/TZStackView,CosynPa/TZStackView