Publish improvements

1. Proper error and notice reporting when using publish email feature.
2. QR codes on publish screen.
3. Chef removed.
4. Error handling in mail send feature in server's index.js.
5. MakeAPI user search endpoint (returns JSON).
if we're reusing, `var codes = document.querySelectorAll('[data-qrcode-for]'); Array.prototype.forEach.call(codes, function(element, index) {  /* L44-49 */ if (element.localName === "a") { /* L55-L58 */ } });` ?