Implement new URN solution
e.g.:
<idno rend="URN;urn:nbn:de:101:1-2018091106130993438235"
type="URL">http://nbn-resolving.de/urn:nbn:de:101:1-2018091106130993438235</idno>
see #24
diff --git a/xslt/epub2i5.xsl b/xslt/epub2i5.xsl
index 734e644..d83e778 100644
--- a/xslt/epub2i5.xsl
+++ b/xslt/epub2i5.xsl
@@ -333,8 +333,8 @@
<idno type="{$type}"><xsl:value-of select="replace(., '(([0-9]|-)+X?).*', '$1')"/></idno>
</xsl:if>
</xsl:when>
- <xsl:when test="$type='URN'">
- <idno rend="URN" type="URN"><xsl:value-of select="."/></idno>
+ <xsl:when test="$type='URL' and contains(., '/urn:nbn:de')">
+ <idno rend="URN;{tokenize(., '/')[last()]}" type="URL"><xsl:value-of select="."/></idno>
</xsl:when>
<xsl:otherwise><idno type="{$type}"><xsl:value-of select="."/></idno></xsl:otherwise>
</xsl:choose>