Turn off incremental linking in all configurations. r=Garf

Incremental linking fails on my unpatched VS2010 compiler
with "failure during conversion to COFF: file invalid or corrupt".
Other than testing both configurations there's no particular
reason to use the option here.

win32/VS2010/opusfile_example.vcxproj

@@ -38,7 +38,7 @@
   </ImportGroup>
   <PropertyGroup Label="UserMacros" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
-    <LinkIncremental>true</LinkIncremental>
+    <LinkIncremental>false</LinkIncremental>
     <IncludePath>..\..\..\opus\include;..\..\..\ogg\include;..\..\include;$(IncludePath)</IncludePath>
     <LibraryPath>..\..\..\opus\win32\VS2010\$(Platform)\$(Configuration)\;..\..\..\ogg\win32\VS2010\$(Platform)\$(Configuration)\;$(VCInstallDir)lib;$(VCInstallDir)atlmfc\lib;$(WindowsSdkDir)lib;$(FrameworkSDKDir)\lib</LibraryPath>
     <OutDir>$(Platform)\$(Configuration)\</OutDir>

win32/VS2010/seeking_example.vcxproj

@@ -38,7 +38,7 @@
   </ImportGroup>
   <PropertyGroup Label="UserMacros" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
-    <LinkIncremental>true</LinkIncremental>
+    <LinkIncremental>false</LinkIncremental>
     <IncludePath>..\..\..\opus\include;..\..\..\ogg\include;..\..\include;$(IncludePath)</IncludePath>
     <LibraryPath>..\..\..\opus\win32\VS2010\$(Platform)\$(Configuration)\;..\..\..\ogg\win32\VS2010\$(Platform)\$(Configuration)\;$(VCInstallDir)lib;$(VCInstallDir)atlmfc\lib;$(WindowsSdkDir)lib;$(FrameworkSDKDir)\lib</LibraryPath>
     <OutDir>$(Platform)\$(Configuration)\</OutDir>