Open one DTP widget at a time

Added line to close all other open widgets before opening a new one on button click. This was default behaviour in BS-DTP (v2.5) working with moment-with-langs (v2.5).

Ideally this would be available as an option with the default set to true (close all others before opening current).

You can check here http://jsfiddle.net/henser/kmbo576p/496/ the working example ... remove line to see current behaviour.

This fix also work for dynamically generated DTP widgets.