Add replacement image. Use png logo

Author: mcarans

installers/flatpak/flatpak_build.sh

@@ -32,4 +32,4 @@ install -D installers/FreeDesktop/oolite.desktop $FLATPAK_DESKTOP
 desktop-file-edit --set-key=Exec --set-value=run_oolite.sh $FLATPAK_DESKTOP
 desktop-file-edit --set-key=Icon --set-value=space.oolite.Oolite $FLATPAK_DESKTOP
 
-install -D installers/flatpak/oolite-logo1.svg /app/share/icons/hicolor/scalable/apps/space.oolite.Oolite.svg
+install -D Resources/Binary/Textures/oolite-logo1.png /app/share/icons/hicolor/256x256/apps/space.oolite.Oolite.png

installers/flatpak/oolite-070A.png

@@ -45,11 +45,11 @@
   <screenshots>
     <screenshot type="default">
       <image>https://raw.githubusercontent.com/OoliteProject/oolite/1.92-maintenance/installers/flatpak/oolite-999.png</image>
-      <caption>Pick your ship. Forge your career. Explore the galaxy.</caption>
+      <caption>The universe awaits. Go explore and seek your fortune!</caption>
     </screenshot>
     <screenshot>
-      <image>https://raw.githubusercontent.com/OoliteProject/oolite/1.92-maintenance/installers/flatpak/oolite-070A.png</image>
-      <caption>Encounter a diverse range of interstellar craft. </caption>
+      <image>https://raw.githubusercontent.com/OoliteProject/oolite/1.92-maintenance/installers/flatpak/oolite-008.png</image>
+      <caption>Choose from a diverse range of interstellar craft. </caption>
     </screenshot>
     <screenshot>
       <image>https://raw.githubusercontent.com/OoliteProject/oolite/1.92-maintenance/installers/flatpak/oolite-064.png</image>