Replaced throw() with BOOST_NOEXCEPT_OR_NOTHROW

With throw(), Visual Studio 2017 emitted a warning "C26439 SPECIAL_NOEXCEPT". Reproducible at least if code analysis was set to level: "Microsoft Native Recommended Rules".

https://docs.microsoft.com/en-us/visualstudio/code-quality/c26439?view=vs-2017

test/helper2.cpp

@@ -20,7 +20,7 @@ boost
             }
 
         derives_boost_exception::
-        ~derives_boost_exception() throw()
+        ~derives_boost_exception() BOOST_NOEXCEPT_OR_NOTHROW
             {
             }
 
@@ -32,7 +32,7 @@ boost
             }
 
         derives_boost_exception_virtually::
-        ~derives_boost_exception_virtually() throw()
+        ~derives_boost_exception_virtually() BOOST_NOEXCEPT_OR_NOTHROW
             {
             }
 
@@ -44,7 +44,7 @@ boost
             }
 
         derives_std_exception::
-        ~derives_std_exception() throw()
+        ~derives_std_exception() BOOST_NOEXCEPT_OR_NOTHROW
             {
             }