desktop: let --convert-to dump its exception message on stderr

Change-Id: Ic906740ddeab04a9acfee997a31a2249f23de65f
diff --git a/desktop/source/app/dispatchwatcher.cxx b/desktop/source/app/dispatchwatcher.cxx
index f26d17c..5b6e911 100644
--- a/desktop/source/app/dispatchwatcher.cxx
+++ b/desktop/source/app/dispatchwatcher.cxx
@@ -562,9 +562,12 @@ bool DispatchWatcher::executeDispatchRequests( const DispatchList& aDispatchRequ
                            {
                                xStorable->storeToURL( aOutFile, conversionProperties );
                            }
                            catch (const Exception&)
                            catch (const Exception& rException)
                            {
                                fprintf( stderr, "Error: Please reverify input parameters...\n" );
                                std::cerr << "Error: Please reverify input parameters...";
                                if (!rException.Message.isEmpty())
                                    std::cerr << " (" << rException.Message << ")";
                                std::cerr << std::endl;
                            }

                            if( aDispatchRequest.aRequestType == REQUEST_CAT )