add nlohmann/json

this will conflict with a change in the http branch, but i dont care
right now

.gitmodules

@@ -21,4 +21,7 @@
 	url = https://github.com/nih-at/libzip
 [submodule "deps/cpp-httplib"]
 	path = deps/cpp-httplib
-	url = https://github.com/yhirose/cpp-httplib
+	url = https://github.com/yhirose/cpp-httplib
+[submodule "deps/json"]
+	path = deps/json
+	url = https://github.com/nlohmann/json

src/TServer.cpp

@@ -7,13 +7,15 @@
 #include <any>
 #include <sstream>
 
+#include <nlohmann/json.hpp>
+
 #include "LuaAPI.h"
 
 #undef GetObject // Fixes Windows
 
 #include "Json.h"
 
-namespace json = rapidjson;
+namespace json = nlohmann::json;
 
 TServer::TServer(const std::vector<std::string_view>& Arguments) {
     beammp_info("BeamMP Server v" + Application::ServerVersionString());