drop contour.spec.namespace, create resources in the same namespace as the Contour CR

[skriss]

Follow-up to #382

We have clarified our policy around alpha APIs to allow fields to be dropped without revving the API version (this diverges slightly from upstream). As such, we are free to go ahead and drop the namespace field from the Contour spec and always create resources in the same namespace as the Contour CR itself, to simplify namespace management.

[sunjayBhatia]

do we still want to transition to using the contour ContourDeployment CRD? if so could be a related change needed to stop using the Contour CRD from the operator, move the required fields over, etc.

[skriss]

do we still want to transition to using the contour ContourDeployment CRD? if so could be a related change needed to stop using the Contour CRD from the operator, move the required fields over, etc.

Good question, not sure of the answer but agree that if we are going to do that migration then we should make this change as part of that.