Bug 8252: Fix indexing of UNIMARC 1xx for DOM

Bug 8252: Fix indexing of UNIMARC 1xx for DOM

This patch makes the same changes in UNIMARC DOM configuration as patch
1 made for GRS-1.

positions of subfields are indexed that way :
In biblio-koha-indexdefs.xml :
tag="100" subfields="a" offset="17" length="1"
In biblio-zebra-indexdefs.xsl :
xslo:value-of select="substring(., 17, 1)"

I had to edit biblio-zebra-indexdefs.xsl by hand, because
etc/zebdradb/xml/koha-indexdefs-to-zebra.xsl does only support
"subtring" in handle-one-index-control-field template.

It is good for MARC21, but not for UNIMARC : in MARC21, indexing
subtrings is needed for controled field (001-009, with no subfields)
But in UNIMARC it is needed for subfields of 1XX fields.
So if DOM indexing is working with these new files, we may need to
change koha-indexdefs-to-zebra.xsl.

Test plan (not possible in a sandbox) :
1) In a Koha instance using UNIMARC and DOM indexing
2) Apply Patch 1 and Patch 2 (this one)
3) Copy the following files from the etc/zebradb directory of your
   source into the etc/zebradb directory of your main Koha directory :
-- etc/zebradb/marc_defs/unimarc/biblios/biblio-koha-indexdefs.xml
-- etc/zebradb/marc_defs/unimarc/biblios/biblio-zebra-indexdefs.xsl
-- etc/zebradb/ccl.properties
-- etc/zebradb/biblios/etc/bib1.att
4) rebuild zebra with -x -b -r -v options
5) check if coded filters in advanced search are usable in OPAC and
   Staff interface

Signed-off-by: Bernardo Gonzalez Kriegel <bgkriegel@gmail.com>
Works. No koha-qa errors.

Test for DOM
Apply patches
Don't forget to copy files
reindex
Search by coded fields works, also Country-publication

Signed-off-by: Jonathan Druart <jonathan.druart@biblibre.com>
Signed-off-by: Galen Charlton <gmc@esilibrary.com>