Expose interfaceOrientation property to ClojureScript
Previously, a compiler warning about not auto-synthesizing this property was squelched by revising it to be a method. But, this has a different calling form from ClojureScript ( . instead of .- ) and this caused a regression. Reintroduce property, preserving the superclass's nonatomic,readonly designators, and add a getter that simply delegates to superclass. This works and eliminates the compiler warning.