||A class all mail view helpers can extend from to ensure they're using
the correct partials folder, etc.
||Render a big call-to-action button.
||This helper renders the white content area that contains the bulk of the
message's actual content. You'd typically open this just after opening
the document itself. You may want to include some supplemental content
after closing this helper but before closing the document, however (e.g.
||This helper renders the HTML document's header and footer. Just call its
open() and close() methods to wrap the remainder of your message's view script.
||Render a footer area for things like unsubscribe links.
||Render an H1.
||Render an H2.
||Render a link (<a>) tag with all the needed inline styles.
||Render a paragraph tag with all the needed inline styles.