Bug 12114: Fix encoding problem with reports JSON web service (opac)

Bug 12114: Fix encoding problem with reports JSON web service (opac)

- catalog a record that includes umlauts äöü
- write a report, that has the record in the result set
- access the JSON output of the report
  <OPAC BaseURL/cgi-bin/koha/svc/report?id=1
- verify the umlaut displays not correctly
- switch the encoding in the browser to 'western'/latin1
- verify the umlaut now displays correctly
- apply patch
- verify umlaut now displays correctly from the beginning

Based on paste from Galen Charlton.

Followed test plan. Result as expected.
Signed-off-by: Marc Véron <veron@veron.ch>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Galen Charlton <gmc@esilibrary.com>