Add more destination symbols

[daganzdaanda]

On https://wiki.openstreetmap.org/wiki/Key:destination:symbol#Value_list there's a list that has a lot of symbols. I've read https://github.com/mueschel/OsmLaneVisualizer/blob/master/_destinationsigns.scss and it looks like only a small number of signs are currently there. Would it be possible to adapt the existing symbols from the wiki (as long as they are SVGs)?

I've also found on Wikipedia Symbole der Richtlinien für die wegweisende Beschilderung auf Autobahnen 2000 (RWBA 2000) which has the official symbols for Germany's motorways, and in the next section, for other roads. These symbols all are SVG files.

[mueschel]

I didn't take the time to add all of the documented symbols yet. If you like to help, you're very welcome. As you said, we just need a link to the images - just make sure they are really in the public domain and don't need attribution.

Related: https://github.com/mueschel/OsmDestinationToSVG/issues/4