Bug 8252: Followup for Date/time-last-modified and Music number

Bug 8252: Followup for Date/time-last-modified and Music number

This followup restores the original wording of "Date/time-last-modified"
index, and change the name of "Music-number" index to
"Number-music-publisher"

To test :
1. In a UNIMARC Koha instance
2. Apply patchs #1, #2 and this followup
3. Copy from src/etc/zebradb directory to the etc/zebradb/ in your main
   Koha directory the following files:
-- zebradb/biblios/etc/bib1.att
-- zebradb/ccl.properties
-- zebradb/marc_defs/unimarc/biblios/record.abs
-- zebradb/marc_defs/unimarc/biblios/biblio-koha-indexdefs.xml
-- zebradb/marc_defs/unimarc/biblios/biblio-zebra-indexdefs.xsl
4. Rebuild zebra with -b -x -v -r options
5. Write a value like "test071a" in 071$a field in a record
6. Check if you can find this record with this search:
   "ccl=Number-music-publisher:test071a"

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

Test
Copy files
reindex full
Modify a couple of record to add 071a with test message
Reindex -v -z -b -x
Search test message as described and found modified records.

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