Replacing cave entry PNG icon with SVG version

[kocio-pl]

Implements part of #1165.

Simple substitution of PNG, since I think it works good already:

[nebulon42]

Is it? Looks more symmetrical, but good.

[kocio-pl]

Well, I just recreated it with circles because from what I saw it was more or less circular, but didn't make any pixel peeping. =} I mean fast design copy, not exact shape.

[kocio-pl]

Looks like it's not about symmetry, but rather stretched up, so the other possible version could be something like this:

[kocio-pl]

Oh, it's not that simple - under further inspection I think it is side-stretched, but at the same time overall "triangular" shape. I will try to recreate it later to see if it's better than shape based on a regular circle.

[HolgerJeromin]

Is this no Sjjb icon where you can get the source?
But I am not sure if your current circle version is just as good as the original.

[kocio-pl]

I guess this is much better:

and here is original SJJB icon reworked for comparison:

Which one do you prefer?

[daganzdaanda]

The second one tries to be naturalistic, but we usually have our icons clean and more abstract. So I favour the first one.