Form field label separated from key

[israelins85]

My proposal is create an attribute label optional for the field text, to separate from key.
This make easy use the key as the field name and at label the translatable name of the field.
To keep the translation file organised I'm using the translations string like "auth.fields.password", but this make the key be dependent of this same syntax.

[agordn52]

Thanks for contribution on this in nylo-core/support#35
It's now all merged in 🚀