Bug 20747: DB Rev

This patch adds a DB rev to update the system preference in existing installations.

 # Please enter the commit message for your changes. Lines starting

Signed-off-by: Jason Robb <jrobb@sekls.org>
Signed-off-by: Brendan Lawlor <blawlor@clamsnet.org>
Signed-off-by: Matt Blenkinsop <matt.blenkinsop@openfifth.co.uk>
Signed-off-by: Katrin Fischer <katrin.fischer@bsz-bw.de>

installer/data/mysql/db_revs/bug_20747-updatelocalholdspriority_syspref.pl

@@ -0,0 +1,25 @@
+use Modern::Perl;
+
+return {
+    bug_number  => "20747",
+    description => "Allow LocalHoldsPriority to fill by hierarchical groups system rather than individual library ",
+    up          => sub {
+        my ($args) = @_;
+        my ( $dbh, $out ) = @$args{qw(dbh out)};
+        my $local_holds_priority = C4::Context->preference('LocalHoldsPriority');
+
+        # Do you stuffs here
+        $dbh->do(
+            q{
+            UPDATE systempreferences
+            SET options='GiveLibrary|None|GiveLibraryGroup|GiveLibraryAndGroup',
+                value=CASE value WHEN '1' THEN 'GiveLibrary' ELSE 'None' END,
+                type="Choice"
+            WHERE variable="LocalHoldsPriority"
+            'Enables the LocalHoldsPriority feature', 'None'  'Choice'),
+        },
+        );
+
+        say $out "Updated system preference 'LocalHoldsPriority'";
+    },
+};