Add smoke test for Gradle compatibility

src/test/java/com/thealiamalia/exposebankstate/ExposeBankStateSmokeTest.java

@@ -0,0 +1,13 @@
+package com.thealiamalia.exposebankstate;
+
+import org.junit.Test;
+import static org.junit.Assert.*;
+
+public class ExposeBankStateSmokeTest
+{
+  @Test
+  public void smoke()
+  {
+    assertTrue(true);
+  }
+}