Make amenity=shelter brown

[kocio-pl]

Observed in the German style.

Changes proposed in this pull request:

• Make amenity=shelter brown, as it is not a transport nor accommodation utility, rather generic amenity

It looks more like other amenities on platforms and doesn't take away attention from real transport-related objects:

Before

After

It blends better with other amenities at the picnic site and with buildings:

Before

After

It's also easier to spot in the forest:

Before

After

[matthijsmelissen]

Black (like towers and hunting stands) and green would also options for me.

Brown rather suggests some more active staffed facility to me, given most of the other brown objects.

Anything is better than blue though.

[kocio-pl]

I would not use man made black, since they are useful for general public, unlike the objects you've mentioned, which are mostly landmarks. Green suggests some kind of leisure and has similar brightness as blue. Similarity to small trash cans on platform and picnic tables is what makes me think that brown is the best.