Launcher improvements

Launcher windows are more Starter-like now:
- The scenery picker, vehicle list and keymapper buttons are now tied to the top portion of the screen.
- The current window is spanning the entire rest of the screen.
- Scenarios are now grouped into categories in the exact same way as Starter does.
- Some drawbacks include:
  - Currently you cannot edit the current trainset, as the vehicle picker window overwrites the scenario list window.
  - The GUI doesn't update when the screen resolution is changed.

launcher/vehicle_picker.h

@@ -2,6 +2,7 @@
 
 #include "uilayer.h"
 #include "textures_scanner.h"
+#include "translation.h"
 
 namespace ui {
 
@@ -10,7 +11,7 @@ class vehiclepicker_panel : public ui_panel
   public:
 	vehiclepicker_panel();
 
-	void render() override;
+	void render_contents() override;
 
 private:
 	bool selectable_image(const char *desc, bool selected, const deferred_image *image, const skin_set *pickable = nullptr);
@@ -22,6 +23,24 @@ private:
 	bool display_by_groups = true;
 	deferred_image placeholder_mini;
 	std::array<char, 128> search_query = { 0 };
+	std::map<vehicle_type, std::string> type_names =
+	{
+		{ vehicle_type::electric_loco, STRN("Electric locos") },
+		{ vehicle_type::diesel_loco, STRN("Diesel locos") },
+		{ vehicle_type::steam_loco, STRN("Steam locos") },
+		{ vehicle_type::railcar, STRN("Railcars") },
+		{ vehicle_type::emu, STRN("EMU") },
+		{ vehicle_type::utility, STRN("Utility") },
+		{ vehicle_type::draisine, STRN("Draisines") },
+		{ vehicle_type::tram, STRN("Trams") },
+		{ vehicle_type::carriage, STRN("Carriages") },
+		{ vehicle_type::truck, STRN("Trucks") },
+		{ vehicle_type::bus, STRN("Buses") },
+		{ vehicle_type::car, STRN("Cars") },
+		{ vehicle_type::man, STRN("People") },
+		{ vehicle_type::animal, STRN("Animals") },
+		{ vehicle_type::unknown, STRN("Unknown") }
+	};
 
 	vehicles_bank bank;