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-8.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="8"
+   height="8">
+  <path
+     style="fill:#fdfdfc;stroke:#525244;stroke-width:1"
+     d="m 7.5,4 a 3.5,3.5 0 0 1 -7,0 3.5,3.5 0 1 1 7,0 z" />
+  <path
+     style="fill:#525244;fill-opacity:1;stroke:none"
+     d="m 5.5,4 a 1.5,1.5 0 0 1 -3,0 1.5,1.5 0 1 1 3,0 z" />
+</svg>