OSM OpenMapTiles style (#1420)

* OpenMapTiles style

* Rename style snippets from layer_name.json to defaultstyle.json

* Add README to icons dir.

* Add README to icons dir.

* Rename snippets to style.json

* Fix spritezero - move icons to svg subdir

* Move icons from style/icons/svg directly to style/icons

Co-authored-by: Tomas Pohanka <TomPohys@gmail.com>

style/icons/place-capital-6.svg

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<svg
+   xmlns="http://www.w3.org/2000/svg"
+   version="1.1"
+   width="6"
+   height="6">
+  <path
+     style="fill:#fdfdfc;stroke:#575749;stroke-width:1"
+     d="m 5.5,3 a 2.5,2.5 0 0 1 -5,0 2.5,2.5 0 1 1 5,0 z" />
+  <path
+     style="fill:#575749;stroke:none"
+     d="M 4,3 A 1,1 0 0 1 2,3 1,1 0 1 1 4,3 z" />
+</svg>