Improve conref XSLT
Improve conref XSLT

- Replace long reused expressions with a variable.
- Combine multiple consecutive xsl:value-of elements.
- Use xsl:with-param select attribute.
- Reorder XPath expression predicates to test id first.
zanyants/dita-ot,doctales/dita-ot,queshaw/dita-ot,dita-ot/dita-ot,shaneataylor/dita-ot,doctales/dita-ot,eerohele/dita-ot,jelovirt/muuntaja,shaneataylor/dita-ot,shaneataylor/dita-ot,Hasimir/dita-ot,robander/dita-ot,queshaw/dita-ot,shaneataylor/dita-ot,doctales/dita-ot,zanyants/dita-ot,jelovirt/muuntaja,zanyants/dita-ot,eerohele/dita-ot,queshaw/dita-ot,drmacro/dita-ot,Hasimir/dita-ot,jelovirt/muuntaja,infotexture/dita-ot,dita-ot/dita-ot,infotexture/dita-ot,dita-ot/dita-ot,robander/dita-ot,doctales/dita-ot,robander/dita-ot,drmacro/dita-ot,infotexture/dita-ot,drmacro/dita-ot,infotexture/dita-ot,eerohele/dita-ot,dita-ot/dita-ot,Hasimir/dita-ot,infotexture/dita-ot,queshaw/dita-ot,Hasimir/dita-ot,dita-ot/dita-ot,robander/dita-ot,zanyants/dita-ot,shaneataylor/dita-ot,eerohele/dita-ot,drmacro/dita-ot,robander/dita-ot,drmacro/dita-ot