PR for issue #1996, enhance _.bindAll

[bishopZ]

No description provided.

[megawac]

Use flatten() as we do in omit and pick

So something like

function bindAll(obj) {
    var keys = flatten(arguments, false, false, 1);
    var index = keys.length;
    if (index < 1) throw new Error('bindAll must be passed function names');
    while (index--) {
      obj[keys[index]] = _.bind(obj[keys[index]], obj);
    }
    return obj;
};

Also add some tests svp 😺

[jridgewell]

Closing in favor of #2141.