Include official boost-free asio module.

.gitmodules

@@ -5,3 +5,6 @@
 [submodule "deps/json11"]
 	path = deps/json11
 	url = https://github.com/dropbox/json11.git
+[submodule "deps/asio"]
+	path = deps/asio
+	url = https://github.com/chriskohlhoff/asio.git

deps/asio

@@ -0,0 +1 @@
+Subproject commit 722f7e2be05a51c69644662ec514d6149b2b7ef8

premake5.lua

@@ -86,9 +86,9 @@ workspace "iw4x"
 		pchheader "STDInclude.hpp" -- must be exactly same as used in #include directives
 		pchsource "src/STDInclude.cpp" -- real path
 
-		-- Dependency on zlib
+		-- Dependency on zlib, json11 and asio
 		links { "zlib", "json11" }
-		includedirs { "./deps/zlib", "./deps/json11" }
+		includedirs { "./deps/zlib", "./deps/json11", "./deps/asio/asio/include"  }
 
 		-- Virtual paths
 		if not _OPTIONS["no-new-structure"] then

src/STDInclude.hpp

@@ -30,7 +30,9 @@
 
 // Submodules
 #define ZLIB_CONST
+#define ASIO_STANDALONE
 #include <zlib.h>
+#include <asio.hpp>
 #include <json11.hpp>
 
 // Version number