Bug 13992: Software error in reports if field or table does not exist

Bug 13992: Software error in reports if field or table does not exist

To reproduce:

- Go to Home > Reports Guided reports wizard
- Create report from SQL
- Enter something like: select holdrio from borrowers
- Save SQL
- run report

Result:
Can't use an undefined value as an ARRAY reference at /usr/share/kohaclone/reports/guided_reports.pl line 932.
expected: graceful error message

- Change sql to something like: select id from holdrio;
- Save SQL
- Run report

Result:
Can't use an undefined value as an ARRAY reference at /usr/share/kohaclone/reports/guided_reports.pl line 932.
expected:  graceful error message

- Change sql to something like: pling from plong
- Save SQL
Result (after saving): Message "The database returned the following error: 1"
Expected: Meaningful message "The database returned the following error: No SELECT" (similar to forbidden statements as UPDATE)

Test plan:
- Apply patch
- Try to reproduce issues above. They should be resolved.

Signed-off-by: Nick Clemens <nick@quecheelibrary.org>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>