DS-1917 JSPUI validity fixes (several non-controversial fixes)
edited for junii2 version 3.1
[DS-2005] Discovery hit highlighting issue with abstracts/fulltext
DS-2064 METS ingester doesn't check if the files in the zip exist.
DS-2067 DRI rend attribute not processed in side bar items.
Merge pull request #516 from zuki/junii2-3-1

DS-2100 junii2 OAI crosswalk version 3.1
Merge pull request #477 from helix84/DS-1917-JSPUI-validity-fixes

DS-1917 JSPUI validity fixes (several non-controversial fixes)
Update database_schema_3-4.sql

Found version mismatch text inside the postgres 3 to 4 upgrade command, mentioned 18to3
DS-2104 Only clear metadata for qualifiers actually present

This is a bug fix for an issue where metadata values could disappear during
submission or in the workflow when a qualdrop input item is placed on a
different page from another input item for the same schema+element. The
previous version of this code processed a page by removing all metadata values
from the item for fields listed on that page. For qualdrop inputs, metadata
values for all qualifiers (including no qualifier) were removed rather than
just those qualifiers actually listed in the qualdrop. This bugfix changes the
code to use the qualifiers from the value pairs of the qualdrop.
Merge pull request #607 from aschweer/DS-2104-disappearing-metadata

DS-2104 Only clear metadata for qualifiers actually present
Merge pull request #576 from rivaldi8/DS-2067-rend-not-processed

DS-2067 DRI rend attribute not processed in side bar items.
Merge pull request #571 from rivaldi8/DS-2064-sword-file-missing-in-zip

DS-2064 METS ingester doesn't check if the files in the zip exist.
Merge pull request #536 from KevinVdV/DS-2005

[DS-2005] Discovery hit highlighting issue with abstracts/fulltext