ICallbackResponseBuilder + added more unit-tests (#101)

* Callback

* Add more tests

test/WireMock.Net.Tests/Matchers/ExactObjectMatcherTests.cs

@@ -0,0 +1,23 @@
+using NFluent;
+using WireMock.Matchers;
+using Xunit;
+
+namespace WireMock.Net.Tests.Matchers
+{
+    public class ExactObjectMatcherTests
+    {
+        [Fact]
+        public void ExactObjectMatcher_GetName()
+        {
+            // Assign
+            object obj = 1;
+
+            // Act
+            var matcher = new ExactObjectMatcher(obj);
+            string name = matcher.GetName();
+
+            // Assert
+            Check.That(name).Equals("ExactObjectMatcher");
+        }
+    }
+}