Update tree icons

[tordans]

The new tree presets from #956 are great to get more detailed trees on the map a lot easier.

However, especially the unspecified tree icon can be improved. @bhousel created a new set of icons in rapideditor/temaki#87 which this PR applies. (Temaki release 5.6.)

Preview of icons: https://rapideditor.github.io/temaki/docs/ => "tree"

Let's see how they look on the map in the preview…

Todos:

• The icons don't show. ==> This requires Update temaki icon library to 5.6 iD#9953
• The drop-down icons need Toben updated as well ==> Done

[github-actions]

🍱 Preview the tagging presets of this pull request here: https://pr-1035--ideditor-presets-preview.netlify.app/id/dist/#locale=en.

[tyrasd]

I'm not really convinced that using the temaki-tree_leafless icon is a good idea: It does not look great IMO, could be confused with a dead tree, and is just fundamentally not a good fit for the "unspecified tree type" preset: it is actually more a representation of a tree with leaf_cycle=deciduous which is an attribute we do not want to directly depict with that preset.

But let's talk about what we could do instead:

• Option A: To be honest, Maki's park icon (and this copy of it) always reminded me of a stone pine tree (Punis pinea), which interestingly is actually a needleleaved tree (thinking about it… it is not very typical for broadleaved trees to have long exposed branches, maybe that's why). But I do of course also see the resemblance of the characteristic bushy crown of many broadleaved tree types. Maybe it was even originally the intention of Maki's designers to have a tree icon that can fit many different varieties perhaps?!

  So, perhaps it could be a better candidate for the generic tree icon than the one from Röntgen (which I, btw, partially chose because it also resembles both typical broadleaved trees as well as vaguely the shape of a cupressus tree). In this case, the only thing missing would be an icon for a "simple" broadleaved tree, maybe something like https://www.svgrepo.com/svg/354697/tree-deciduous-14

• Option B: I would be OK with an icon which has a bushy half and a spiky half. But I would guess that it is not easy to make such an icon look reasonably well.

• Option C: something else?

[tordans]

Closing this. I don't see a good way forward for now. We will need to think about the icons more…