Convert a[@target='_blank'] to a[@rel='external']

gistfile1.xml

<!-- Addition to the ninja XSL utility -->
<xsl:template match="a[@target='_blank']" mode="html">
    <a>
        <xsl:attribute name="rel">external</xsl:attribute>
        <xsl:apply-templates select="* | @*[not(name()='target')] | text()" mode="html"/>
    </a>
</xsl:template>

<!-- Provide an alt-tag for images with no alt-tag: -->
<xsl:template match="img[not(@alt) or @alt = '']" mode="html">
    <xsl:element name="{name()}">
        <xsl:apply-templates select="* | @* | text()" mode="html"/>
        <xsl:attribute name="alt">
            <xsl:value-of select="concat('Image of ', $website-name)" />
        </xsl:attribute>
    </xsl:element>
</xsl:template>