Default implementation for Requester::message()

This is what many sub-classes do (or should)
so lets prepare to remove some boilerplate.

src/misc/requester.cpp

@@ -9,6 +9,7 @@
  */
 #include <string>
 #include <cstdio>
+#include <iostream>
 
 #define epicsExportSharedSymbols
 #include <pv/lock.h>
@@ -34,6 +35,9 @@ string getMessageTypeName(MessageType messageType)
     return messageTypeName[messageType];
 }
 
-
+void Requester::message(std::string const & message,MessageType messageType)
+{
+    std::cerr << "[" << getRequesterName() << "] message(" << message << ", " << getMessageTypeName(messageType) << ")\n";
+}
 
 }}