Set release project to use MBCS, not UNICODE (UCS-2).

Debug project was already set this way.

src/comio/comio.vcxproj

@@ -18,7 +18,7 @@
     <ProjectGuid>{79CF784E-4438-4FCC-9B7A-10ACB716C948}</ProjectGuid>
     <Keyword>Win32Proj</Keyword>
     <RootNamespace>comio</RootNamespace>
-    <WindowsTargetPlatformVersion>10.0</WindowsTargetPlatformVersion>
+    <WindowsTargetPlatformVersion>7.0</WindowsTargetPlatformVersion>
   </PropertyGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.Default.props" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="Configuration">
@@ -32,7 +32,7 @@
     <UseDebugLibraries>false</UseDebugLibraries>
     <PlatformToolset>v141_xp</PlatformToolset>
     <WholeProgramOptimization>true</WholeProgramOptimization>
-    <CharacterSet>Unicode</CharacterSet>
+    <CharacterSet>MultiByte</CharacterSet>
   </PropertyGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.props" />
   <ImportGroup Label="ExtensionSettings">