Fix attributes on Function.prototype
Fix attributes on Function.prototype

‘typeof Function.prototype’ was reporting ‘object’, should be a ‘function’.  Also, `new Function.prototype()` was succeeding, should throw.  This particular object has to be built manually since it is bootstrapping Function.

NeilFraser/JS-Interpreter,NeilFraser/JS-Interpreter,NeilFraser/JS-Interpreter