[html4all] For Q (quotation) and BLOCKQUOTE a 'marks' content markup attribute

[Robert J Burns]

For Q (quotation) and BLOCKQUOTE a 'marks' content markup attribute.  
Permits authors greater control over the separation of concerns of  
styling quotations and specifying the semantics of quotations within a  
document. Also allows authors to work around the current state of  
interoperability across popular UAs.

<http://esw.w3.org/topic/HTML/AddedAttributeQuotationMarks>