Use duration in insight::Event, add chrono_util

Builds/VisualStudio2012/beast.vcxproj

@@ -90,6 +90,7 @@
     <ClInclude Include="..\..\beast\boost\ErrorCode.h" />
     <ClInclude Include="..\..\beast\ByteOrder.h" />
     <ClInclude Include="..\..\beast\chrono\chrono_io.h" />
+    <ClInclude Include="..\..\beast\chrono\chrono_util.h" />
     <ClInclude Include="..\..\beast\chrono\CPUMeter.h" />
     <ClInclude Include="..\..\beast\chrono\abstract_clock.h" />
     <ClInclude Include="..\..\beast\chrono\manual_clock.h" />

Builds/VisualStudio2012/beast.vcxproj.filters

@@ -1239,6 +1239,9 @@
     <ClInclude Include="..\..\beast\make_unique.h">
       <Filter>beast</Filter>
     </ClInclude>
+    <ClInclude Include="..\..\beast\chrono\chrono_util.h">
+      <Filter>beast\chrono</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="..\..\modules\beast_core\containers\DynamicObject.cpp">