* separate css into several files by topic, move all css into assets
Make separate files for all css topics like leaflet and move its into
the assets folder.
This way only one include from index.ts points to an index.tsx in assets
including all the css files.
* fix up compiling
* extract more css imports, unify imports in a css.tsx file
* separate external css & internal css
* renamed icons.css in marker-icons.css
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Co-authored-by: Anton Tranelis <mail@antontranelis.de>
