Removed popstate handling as it proved too eager

Popstate handling also triggered when navigating through Mendix UI so
removed for now

Improvements for browseractions

Widget now also works:
- when using include mode and browser back button
- when the user refreshes the page
- when the user closes the tab in Chrome (other browser already worked)

Added "include" mode

Now it's possible to choose between defining a list of buttons to
exclude from the widget or to include. When you use "include" the widget
will only trigger if the user navigates away from the page with one of
the selected buttons, making it less likely to trigger the widget
unintentionally.

Update exclude func