moved std::to_string to util.h from android

HTTP.cpp

@@ -10,13 +10,6 @@
 #include <algorithm>
 #include <ctime>
 
-#ifdef ANDROID
-#  include "to_string.h"
-#  include <errno.h>
-#else
-#  define to_string(x) std::to_string(x)
-#endif
-
 namespace i2p {
 namespace http {
   const std::vector<std::string> HTTP_METHODS = {
@@ -187,11 +180,7 @@ namespace http {
         out += user + "@";
       }
       if (port) {
-#ifndef ANDROID
-        out += host + ":" + to_string(port);
-#else
-        out += host + ":" + tostr::to_string(port);
-#endif
+        out += host + ":" + std::to_string(port);
       } else {
         out += host;
       }
@@ -349,11 +338,7 @@ namespace http {
     if (status == "OK" && code != 200)
       status = HTTPCodeToStatus(code); // update
     if (body.length() > 0 && headers.count("Content-Length") == 0)
-#ifndef ANDROID
-        add_header("Content-Length", to_string(body.length()).c_str());
-#else
-        add_header("Content-Length", tostr::to_string(body.length()).c_str());
-#endif
+        add_header("Content-Length", std::to_string(body.length()).c_str());
     /* build response */
     std::stringstream ss;
     ss << version << " " << code << " " << status << CRLF;