Add an icon option to confirmButton and add it to ToolbarHelper

[neo314]

Adding it to toolbar helper is an after thought, but, for example, I am using a confirmation button which I want to name "resend" but in order to get an icon, I have to name it "mail". If I use resend I get the id of the button as toolbar-resend (good), but the span of icon-resend (useless). It would be ideal to separate the icon from the name.