JS UTF8 ecnode/decode enhancement

Currently you can not decode UTF8 in JS. According to this http://ecmanaut.blogspot.ca/2006/07/encoding-decoding-utf8-in-javascript.html it is easy to fix.
Not sure where it should go since it is JS only. But in testing std/haxe/Utf8.hx change
public static function decode( s : String ) : String {
return untyped decodeURIComponent(escape(s));
//throw “Not implemented”;
}
public static function encode( s : String ) : String {
return untyped unescape(encodeURIComponent(s));
//throw “Not implemented”;
}

You’d need to add a Utf8.hx file in haxe/std/js/_std/haxe at development · HaxeFoundation/haxe · GitHub for a js specific version.

Platform specific versions of the std files are in std/target/_std and are optional.