NewOptions return an Options instance with default value.

NewPremailer return a new instance of Premailer It take a Document as argument and it shouldn't be nil.

NewPremailerFromBytes take in a document in byte and create a goquery.Document and then create and Premailer instance.

NewPremailerFromFile take an filename Read the content of this file and create a goquery.Document and then create and Premailer instance.

NewPremailerFromString take in a document in string format and create a goquery.Document and then create and Premailer instance.

Options for controlling behaviour.

Premailer is the inteface of Premailer.