Tweaked spawn times / Liquid bridge fixes

core/src/io/anuke/mindustry/maps/Sectors.java

@@ -136,7 +136,6 @@ public class Sectors{
         double waveChance = 0.3;
 
         sector.difficulty = (int)(Mathf.dst(sector.x, sector.y));
-        sector.spawns = sector.missions.first().getWaves(sector);
 
         if(sector.difficulty == 0){
             sector.missions.add(new WaveMission(10));
@@ -145,6 +144,8 @@ public class Sectors{
                     : new BattleMission());
         }
 
+        sector.spawns = sector.missions.first().getWaves(sector);
+
         //add all ores for now since material differences aren't well handled yet
         sector.ores.addAll(Items.tungsten, Items.coal, Items.lead, Items.thorium, Items.titanium);
     }