Tool/Header: Add JSON output mode; game data

Source/Core/DolphinTool/DolphinTool.vcxproj

@@ -39,6 +39,7 @@
   <Import Project="$(ExternalsDir)fmt\exports.props" />
   <Import Project="$(ExternalsDir)liblzma\exports.props" />
   <Import Project="$(ExternalsDir)mbedtls\exports.props" />
+  <Import Project="$(ExternalsDir)picojson\exports.props" />
   <Import Project="$(ExternalsDir)zstd\exports.props" />
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">