Redirect std::uncaught_exception to Catch::uncaught_exception

This means that only one place needs to work with warnings from
the deprecation of `std::uncaught_exception()` in C++17.

Closes #1162.

include/internal/catch_section.cpp

@@ -8,6 +8,7 @@
 
 #include "catch_section.h"
 #include "catch_capture.hpp"
+#include "catch_uncaught_exceptions.h"
 
 namespace Catch {
 
@@ -18,22 +19,15 @@ namespace Catch {
         m_timer.start();
     }
 
-#if defined(_MSC_VER)
-#pragma warning(push)
-#pragma warning(disable:4996) // std::uncaught_exception is deprecated in C++17
-#endif
     Section::~Section() {
         if( m_sectionIncluded ) {
             SectionEndInfo endInfo( m_info, m_assertions, m_timer.getElapsedSeconds() );
-            if( std::uncaught_exception() )
+            if( uncaught_exceptions() )
                 getResultCapture().sectionEndedEarly( endInfo );
             else
                 getResultCapture().sectionEnded( endInfo );
         }
     }
-#if defined(_MSC_VER)
-#pragma warning(pop)
-#endif
 
     // This indicates whether the section should be executed or not
     Section::operator bool() const {