Include MainWindowHandle in the returned ProcessInfo

[mike-eason]

I'm particularly interested in getting the MainWindowHandle integer back from the process info, could you also include that?

So for example, the result would be something like:

var processWindows = require("node-process-windows");

    var activeProcesses = processWindows.getProcesses(function(err, processes) {
        processes.forEach(function (p) {
            console.log("PID: " + p.pid.toString());
            console.log("MainWindowTitle: " + p.mainWindowTitle);
            console.log("ProcessName: " + p.processName);
            ...
            console.log("MainWindowHandle: " + p.mainWindowHandle); // <--- This one pretty please.
        });
    });