Add model conversion tests

system/src/test/scala/ModelToChessTest.scala

@@ -0,0 +1,13 @@
+package lila.system
+
+import model._
+import lila.chess
+
+class ModelToChessTest extends SystemTest {
+
+  "model to chess conversion" should {
+    "new game" in {
+      newGame.toChess must_== chess.Game()
+    }
+  }
+}