Bug 27380: Move get_prepped_report to object and use for svc/reports

Bug 27380: Move get_prepped_report to object and use for svc/reports

This patch moves get_prepped_report to Koha:Report->prep_report
and adds some basic tests

To test:
1 - Using the report created in last test, hit the report svc api like:
http://localhost:8081/cgi-bin/koha/svc/report?id=6&param_name=One&sql_params=One&param_name=Listy|list&sql_params=2345%0D%0A423%0D%0A3%0D%0A2%0D%0A12
2 - Note the use of %0D%0A to separate list params
3 - Test with combinations with and without param_name specified
http://localhost:8081/cgi-bin/koha/svc/report?id=6&sql_params=5&sql_params=2345%0D%0A423%0D%0A3%0D%0A2%0D%0A12

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
JD Amended patch: Perltidy prep_report

Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>