Support for member access expressions with syntax `container.member`, covering cases such as:
* `object.field`
* `object.method(args)`
* `package.namespace.class.member`
* `object.(interface.member)`
* `object.(class.member)`
... and so on. Includes the rule for template name lookup as decided in #949.
Co-authored-by: josh11b <josh11b@users.noreply.github.com>
