added test for private talk

p4/src/test/scala/com/example/p4/PrivateTalkFeatureSpec.scala

@@ -0,0 +1,33 @@
+package com.example.p4
+
+
+import com.example.p4.engine._;
+import com.example.p4.engine.agents._;
+
+import org.scalatest._;
+import org.scalatest.matchers.ShouldMatchers;
+
+class PrivateTalkFeatureSpec extends FeatureSpec
+                               with GivenWhenThen
+                               with ShouldMatchers
+{
+
+	feature("private talk") {
+		scenario(" user A and B try to talk with each other " ) {
+           given("2 users, registered in registry")
+           val user1 = new HumanAgent("u1");
+           val user2 = new HumanAgent("u2");
+           TalkEngine.registry.add( user1 );
+           TalkEngine.registry.add( user2 );
+           TalkEngine.chooseAgent("u1","u2");
+           TalkEngine.chooseAgent("u2","u1");
+           when("message is send to all from one of them")
+           val testMessage = "test-message-1"
+           TalkEngine.dispatch("u1",testMessage);
+           then("others must see one in incoming")
+           val u2m = user1.giveMessageFor(user2.name);
+           assert(u2m.isDefined);			
+		}
+	}
+
+}