Update source to SDL2 2.0.12

Edward Rudd

2020-05-02 03f8528315fa46c95991a34f3325d7b33ae5538c

 source/VisualC/SDLmain/SDLmain.vcxproj

@@ -108,7 +108,6 @@
      <StringPooling>true</StringPooling>
      <RuntimeLibrary>MultiThreadedDLL</RuntimeLibrary>
      <BufferSecurityCheck>false</BufferSecurityCheck>
      <EnableEnhancedInstructionSet>StreamingSIMDExtensions</EnableEnhancedInstructionSet>
      <WarningLevel>Level3</WarningLevel>
      <DebugInformationFormat>OldStyle</DebugInformationFormat>
      <OmitDefaultLibName>true</OmitDefaultLibName>
@@ -143,7 +142,6 @@
      <PreprocessorDefinitions>WIN32;_DEBUG;_WINDOWS;%(PreprocessorDefinitions)</PreprocessorDefinitions>
      <RuntimeLibrary>MultiThreadedDLL</RuntimeLibrary>
      <BufferSecurityCheck>false</BufferSecurityCheck>
      <EnableEnhancedInstructionSet>StreamingSIMDExtensions</EnableEnhancedInstructionSet>
      <WarningLevel>Level3</WarningLevel>
      <DebugInformationFormat>OldStyle</DebugInformationFormat>
      <OmitDefaultLibName>true</OmitDefaultLibName>