Support FirefoxOS & ChromeOS TCP Sockets

[braydonf]

Add integrated support for TCP sockets available in FirefoxOS and ChromeOS:

• https://developer.mozilla.org/en-US/docs/Web/API/TCP_Socket_API
• https://developer.chrome.com/apps/sockets_tcp

Currently possible using "webpack" and "chrome-net" as demonstrated by @throughnothing: #21 (comment)

[throughnothing]

To be clear, my demonstration won't work on a web page in Chrome, as the sockets API (that I'm using at least) is only available to Chrome apps/extensions. To do it from a normal webpage in the browser, I presume we'd have to use WebRTC or WebSockets, or something similar. WebTorrent may be something worth looking at, as it is a peer-to-peer bit-torrent client that can run in the browser using WebRTC for p2p communication.

[braydonf]

Yep, the TCP sockets available in apps and extensions can directly connect to any Bitcoin node, and hybrid nodes are not needed as in the case of WebSocket/WebRTC.