upgraded to C++17 compatibility

examples/exceptionhandling.cxx

@@ -20,19 +20,19 @@ void unexpectedHandler() {
   throw std::bad_exception(); // try to recover
 }
 
-void fn2() throw(std::bad_exception) {
+void fn2() {
   std::cout<<"enter fn2"<<std::endl;
   throw mrw::exception(); // that's wrong, no exception excpected
   std::cout<<"leave fn2"<<std::endl;
 }
 
-void fn1() throw(std::bad_exception) {
+void fn1() {
   std::cout<<"enter fn1"<<std::endl;
   fn2();
   std::cout<<"leave fn1"<<std::endl;
 }
 
-void fn0() throw(std::bad_exception) {
+void fn0() {
   std::cout<<"enter fn0"<<std::endl;
   try {
     fn1();