Fixed server game-over crash

server/src/io/anuke/mindustry/server/ServerControl.java

@@ -86,6 +86,8 @@ public class ServerControl extends Module {
                     Map map = previous;
                     while (map == previous) map = maps.random();
 
+                    if(map != null) {
+
                         info("Selected next map to be {0}.", map.name);
                         state.set(State.playing);
 
@@ -96,6 +98,11 @@ public class ServerControl extends Module {
                         world.loadProceduralMap();
                         logic.play();
                     }
+                }else{
+                    info("Selected a procedural map.");
+                    world.loadProceduralMap();
+                    logic.play();
+                }
             }else{
                 state.set(State.menu);
                 Net.closeServer();