[formatting] add newline to file(s) (#1508)

* Trail appropriate files with a new line

* For some ironic reason it ignored itself

Probably because it wasn’t tracked/commited yet.

* Rename newlines to server executable naming pattern

core/src/mindustry/ui/dialogs/CustomGameDialog.java

@@ -91,4 +91,4 @@ public class CustomGameDialog extends FloatingDialog{
 
         cont.add(pane).uniformX();
     }
-}
+}

core/src/mindustry/ui/layout/BranchTreeLayout.java

@@ -288,4 +288,4 @@ public class BranchTreeLayout implements TreeLayout{
     public enum TreeAlignment{
         center, towardsRoot, awayFromRoot
     }
-}
+}