Add list of actual results to CLITest output when it fails (#494)

This patch adds logging to the `CLITest` so that we know the actual results we got when it fails. It could be that no results are ever returned, or it could be that there is another error and error strings are returned. This patch will learn the cause of the failures.

ksql-cli/src/test/java/io/confluent/ksql/TestRunner.java

@@ -23,6 +23,9 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
 import java.util.Objects;
 
 import static junit.framework.TestCase.fail;
@@ -56,11 +59,15 @@ protected static void test(String command, TestResult.OrderedResult expectedResu
 
   protected static void test(String command, TestResult expectedResult, boolean requireOrder) {
     run(command, requireOrder);
+    final Collection<List<String>> finalResults = new ArrayList<>();
     try {
       TestUtils.waitForCondition(() -> {
         TestResult actualResult = testTerminal.getTestResult();
+        finalResults.clear();
+        finalResults.addAll(actualResult.data);
         return actualResult.data.containsAll(expectedResult.data);
-      }, 10000, "Did not get the expected result '" + expectedResult.toString() + ", in a timely fashion.");
+      }, 10000, "Did not get the expected result '" + expectedResult + ", in a timely fashion. Received " +
+              "following results instead: " + finalResults);
     } catch (InterruptedException e) {
       fail("Test got interrutped when waiting for result " + expectedResult.toString());
     }