addQuote(text, cite) {
        const attrs = Object.assign({}, (cite && { cite }));
        const element = this.wrap('blockquote', text, attrs);
        return this.addRaw(element).addEOL();
    }
Adds an HTML blockquote to the summary buffer

@param {string} text quote text
@param {string} cite (optional) citation url

@returns {Summary} summary instance