Update to logger

logger/doc.go

@@ -3,8 +3,13 @@
   These facilities all currently use the logging library called log15 at
   https://github.com/inconshreveable/log15
 
-  Wrappers for the handlers are written here to provide a kind of isolation layer for Revel
-  in case sometime in the future we would like to switch to another source to implement logging
+	Defining handlers happens as follows
+	1) ALL handlers (log.all.output) replace any existing handlers
+	2) Output handlers (log.error.output) replace any existing handlers
+	3) Filter handlers (log.xxx.filter, log.xxx.nfilter) append to existing handlers,
+	   note log.all.filter is treated as a filter handler, so it will NOT replace existing ones
+
+
 
 */
 package logger