updated README information

examples/pduLog/README.md

 # PDU Log Files
 
-This directory holds temporary files and may be overwritten at any time!
+This directory holds temporary PDU log files which may be deleted at any time!
 
 Each time you run a DIS simulation and a PduRecorder is listening, another
-log file is created.
+log file is created.  File names are numbered sequentially and uniquely, so that 
+important PDU log captures can later be copied and saved to where they are needed.
 
-Be sure to save your work, when appropriate, by copying your log file to
+[ExamplePduCaptureLog.dislog](ExamplePduCaptureLog.dislog) shows an example log file.
+
+Be sure to save your work, when appropriate, by copying log files of interest to
 the corresponding homework or project directory (and likely renaming as well).
 
 Note that the PDU log files are very tolerant of inline comments starting with
-a # character, so you can list success/failure/TODO issues there as well.
+a # character, so you can document success/failure and TODO issues there as well.
+
+To clean out old log files, simply run [build.xml](build.xml) target `clean.all.log.files`