Add CopyCryptestToRoot target

Also see https://www.cryptopp.com/wiki/MSBuild_(Command_Line)#CopyCryptestToRoot

cryptest.vcxproj

@@ -191,6 +191,13 @@
     </PreBuildEvent>
   </ItemDefinitionGroup>
 
+  <!-- Target for Appvoyer                           -->
+  <!-- The rule copies cryptest.exe to the project   -->
+  <!-- root directory so it can be executed in place -->
+  <Target Name="CopyCryptestToRoot">
+    <Exec Command="copy $(Platform)\Output\$(Configuration)\cryptest.exe ."/>
+  </Target>
+
   <!-- Source Files -->
   <ItemGroup>
     <ClCompile Include="adhoc.cpp" />