Oxidizer v0.6.2

Fixed

• Rhai: calling a game method by name is now obj.invoke(method[, args]). The documented obj.call(...) never worked, because Rhai keeps x.call(...) for function pointers ("Data type incorrect: string (expecting Fn)").
• Rhai: a method call on a game property (vehicle.parent.get("MeanRadius")) no longer logs "Property set method not found". Rhai writes such properties back afterwards; an unchanged value is no longer written.