Version 3.1

• Added close() method and closed event (#63)
• Added support for isEnabled (#64)
• [Angular] Compatibility with the new nativescript-angular package (#99)
• [iOS] Fixes compatibility with TNS 3.1 (#107)
• [iOS] Fixes touch problems when touch event is observed on the page (#84)
• [Android] Fixes problems with invisible items in the drop down (#90)
• [iOS] Fixes sizing problems making the drop down invisible when no hint is specified (#104)