fdo#82430 disable SSE2 default of MSVC2012

--- python3/PCbuild/release.props.old	2014-10-01 23:47:33.348095403 +0200
+++ python3/PCbuild/release.props	2014-10-01 23:48:05.051092945 +0200
@@ -9,6 +9,7 @@
   <ItemDefinitionGroup>
     <ClCompile>
       <PreprocessorDefinitions>NDEBUG;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <EnableEnhancedInstructionSet>StreamingSIMDExtensions</EnableEnhancedInstructionSet>
     </ClCompile>
   </ItemDefinitionGroup>
   <ItemGroup>