Layer / POI-Symbol changes

[hbruch]

A couple of changes to the POI- and Layer symbols should be done.

[ ] missing svgs should be created and added to the POI sheet
[ ] for most POI layers, Herrenberg want's (for now) stick with a grey symbol only, no colored circle. In the layer switcher, the symbols should be grey, also
[ ] for cars & bicycle layers, the symbol should get a background circle. For gas stations in cyan background color/white foreground color (like charging stations), rental / repair shops white color / black background color.
[ ] Sharing layers: all symbols (excluding carpool stops) should get an orange, same size circle background
[x] Tourism pin symbol should get lighter stroke (comparable to other top-level icons)

[Denis306]

Can we close or rework this issue @hbruch? I added some answers.

[ ] missing svgs should be created and added to the POI sheet
-> Own ticket already #834
[ ] for most POI layers, Herrenberg want's (for now) stick with a grey symbol only, no colored circle. In the layer switcher, the symbols should be grey, also
-> Obsolete as the decision was made to use the colored circle + icon in the map and the colored Icon only in the map layer switcher. We will be managing that through the POI Layer JSON.
[ ] for cars & bicycle layers, the symbol should get a background circle. For gas stations in cyan background color/white foreground color (like charging stations), rental / repair shops white color / black background color.
-> We will be managing this through the POI Layer JSON.
[ ] Sharing layers: all symbols (excluding carpool stops) should get an orange, same size circle background
-> Is this still relevant?
[x] Tourism pin symbol should get lighter stroke (comparable to other top-level icons)