- making oscimap default backend

- added about-screen
- added TreeTile for Tile lookup, dropping that HashMap
- using simple line-shader instead of std-derivatives one,
  about twice as faster here
- use distance calculation from MapRenderer - removing TileScheduler
- no need for MapGeneratorJob, pass MapTile directly to MapWorkers
- added two-finger tap gestures for zoom-in/out
- added tub/tron rendertheme
- started caching for oscimap
- add x/y coordinates to MapPosition, using it in MapRenderer
- create tag hash when needed
- no need for long tile coordinates max zoomlevel 31 should suffice

res/values/strings.xml

@@ -1,8 +1,8 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <resources>
 	<string-array name="preferences_map_generator_values">
-	  <item>Mapfile</item>
-		<item>PostGIS</item>
+	<!--   <item>Mapfile</item> -->
+	 <item>PostGIS</item> 
 		<item>OpenScienceMap</item>
 	</string-array>
 
@@ -59,6 +59,7 @@
 	<string name="menu_preferences">Preferences</string>
 	<string name="menu_render_theme">Render theme</string>
 	<string name="menu_render_theme_osmarender">Default Theme</string>
+	<string name="menu_render_theme_tronrender">Tube Theme</string>
 	<string name="menu_render_theme_select_file">Select XML file …</string>
 	<string name="menu_screenshot">Screenshot</string>
 	<string name="menu_screenshot_jpeg">JPEG (lossy)</string>