Add logging for missing application stack in JAXRSConfiguration

Information is useful when there is more than one stack, but this information is missing.

pic-sure-api-war/src/main/java/edu/harvard/dbmi/avillach/JAXRSConfiguration.java

@@ -41,6 +41,7 @@ private void initializeApplicationStack() {
             ctx.close();
         } catch (NamingException e) {
             // Currently, this parameter is optional and only used if there is more than one application stack.
+            logger.info("No application stack found. This is only a problem if there is more than one application stack.");
             application_stack = null;
         }
     }