Add support for the community-operator to be installed into a specified namespace when the community-operator is used as a subchart dependency.

There is no support for a namespace override in the community-operator chart, so there is no possibility of setting the namespace from a parent chart. While another solution such as helmfile could be used instead of helm, that add another level of complexity in tooling. By supplying a operator.namespaceOverride value in the chart and using that in the templates, the solution can be supported with just helm.