Update emsdk version, and enable multithreading on web

include/Helpers/FileDownloader.hpp

@@ -2,6 +2,10 @@
 #include <memory>
 #include <functional>
 #include <atomic>
+#include <string>
+#include <fstream>
+#include <sstream>
+#include <algorithm>
 
 #ifndef __EMSCRIPTEN__
     #include <mutex>

include/Helpers/FileDownloaderEmscripten.cpp

@@ -2,6 +2,7 @@
 #include "FileDownloader.hpp"
 #include <cstdio>
 #include <iostream>
+#include <vector>
 
 std::vector<FileDownloader::DownloadHandler> FileDownloader::currentDownloads;