Added ability to export Graph to SVG/PNG
It is now possible to download a snapshot of what is currently displayed in the graph - which also includes modifications like a disabled visual range or a zoomed in state - both as a PNG and a SVG file. For this purpose, two buttons have been added to the top of the visualization's page.
Additionally, the name of the currently opened file is now displayed in the title bar of the browser, in order to make it easier to discern which file has been opened if one uses multiple instances of the visualization.
Closes #84