Add support for Windows, mac and Web

[rupamking1]

Add support for Windows, mac and Web

[jumperchen]

This server side library can work on Windows, Mac, and Linux env. which is the same as Dart VM.

[rupamking1]

Can I use this library as Client in Windows, mac and Web

[jumperchen]

No, for socket.io-client, you should use https://github.com/rikulo/socket.io-client-dart.
This library is used as a server to manage all socket client connections.