Make inclusion of FlexSpy library optional

Remove reference to FlexSpy library from FunFX source code so that no compile error is produced if project is built without FlexSpy library. It is possible to replace the reference with a dynamic one so that opening FlexSpy is possible exactly when the library is included.

Example source code: try { var flexSpy:Object = getDefinitionByName("com.flexspy.FlexSpy"); if (flexSpy != null) flexSpy.show(); } catch (error:ReferenceError) { trace("Could not open FlexSpy!"); }