Add a note about unit-testing

Author: linas

README.md

@@ -76,6 +76,17 @@ Running
 * Start the opencog face-tracking node in the `face_track` directory.
 
 
+Unit Testing
+------------
+There is a simple test driver in `src/unit-test.scm`. It emulates the
+appearance and disappearance of two faces every few minutes. It also
+emulates chat-start and chat-stop.  It does not need or use the regular
+face-tracker or vision system nor the chatbot.  If everything is
+working, the blender head should wak up, smile, react appropriately,
+and then fall asleep every 3-4 minutes.  This test runs in an infinite
+loop.
+
+
 GUI Requirements
 ----------------
 A GUI is needed to edit the beavior tree. Some notes about the

src/unit-test.scm

@@ -1,8 +1,12 @@
 ;
-; Random under-documented unit-test scriptlets.
+; Random under-documented unit-test scriptlet.
+;
+; Neither the vision subsystem, nor the chat subsystem needs to be
+; started to run this test. Just start the behavior tree, then
+; `rlwrap telnet localhost 17020` then
+; `(load "unit-test.scm")`  and then
+; `(run-face-test)`
 ;
-
-
 ; Run a unit test in a separate thread: add faces, chat, remove faces.
 ; These faces don't have corresponding 3D coords, the face-tracker will
 ; not know about them, so you can't use the facetracker while runing