Enhanced htlog.cgi documentation explaining use of parameters

README.md

 
 ##htlog.cgi##
 
-Collects GET requests with parameters *msg* and *tag* and logs them into single text file
+Collects GET requests with parameters *msg*, *tag* and *i* and logs them into single text file.
+
+*   *msg* is actual message body. It can be used to contain parseable data 
+    like `name=john;age=32;state=il;`
+*   *tag* can be used to identify related messages like those from one test
 
 
 ##htlogger.pm##