Werk #5539: Improved performance of pages showing many graphs

Previously the GUI was loading all graphs in the progress of rendering a view. The view was rendered to the user once the information for all graphs is known. This mechanism made pages that show a lot of graphs load slowly.

With this change the views are now rendered with a place holder for each graph which is a lot faster. After the view has been loaded for the user, the browser starts to render the graphs asynchronously and simultaneously which will also reduce the total time needed for loading.

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