Optionally style bookmark titles

[tgraham-antenna]

XSL 1.1 supports some styling of bookmark titles (aligned with what PDF supports): https://www.w3.org/TR/xsl11/#fo_bookmark-title

I am using this change with (elsewhere):

    <xsl:template name="bookmark.title.style">
      <xsl:param name="key" select="local-name()"/>

      <xsl:if test="$key = 'book'">
        <xsl:attribute name="color">
          <xsl:value-of select="$muk.blue" />
        </xsl:attribute>
        <xsl:attribute name="font-weight">bold</xsl:attribute>
      </xsl:if>
    </xsl:template>