Added middleware logic, readme, and tests.

[ghost]

This PR gives the ability to add middleware to the connect server by taking an array of connect-compatible middleware in the options and appending them to the stack.

var liveServer = require("live-server");

var params = {
    port: 8181, // Set the server port. Defaults to 8080.
    host: "0.0.0.0", // Set the address to bind to. Defaults to 0.0.0.0 or process.env.IP.
    root: "/public", // Set root directory that's being server. Defaults to cwd.
    open: false, // When false, it won't load your browser by default.
    ignore: 'scss,my/templates', // comma-separated string for paths to ignore
    file: "index.html", // When set, serve this file for every 404 (useful for single-page applications)
    wait: 1000, // Waits for all changes, before reloading. Defaults to 0 sec.
    mount: [['/components', './node_modules']], // Mount a directory to a route.
    logLevel: 2, // 0 = errors only, 1 = some, 2 = lots
    middleware: [function(req, res, next) { next(); }] // Takes an array of Connect-compatible middleware that are injected into the server middleware stack
};
liveServer.start(params);

[tapio]

Thanks!