HTML Widgets; Angular-style tags; ng-show now uses a different method of showing the element

Previously, any elements using the "ng-show" Angular-style binding used the jQuery show() method to display themselves.

An issue with the version of jQuery used by HTML Widgets and Portals meant that this would add a "display:block" CSS style to the element. This in turn would mean that if a CSS class applied to the element was "display:flex", the flexbox functionality would no longer work.

The new method simply involves removing the "display" and "visibility" styles that the jQuery hide() method adds.