fixes #1209 adds emptyText to email address field

It seems a string "undefined" came back from Cookies.get instead of undefined? I dont recall seeing this before. Added placeholder text in the input field and therefore removed the title.
How about:
```
var emailAddress = "";
if (Ext.util.Cookies.get('emailField') != "undefined") {
    emailAddress = Ext.util.Cookies.get('emailField') : "";
}
```