Bug 25311: Better error handling when creating a patron

Bug 25311: Better error handling when creating a patron

This is still not ideal but brings a bit of enhancement.

One possible problem is that the patron creation will fail if the
streetnumber field is too long (borrowers.streetnumber is varchar(10).

Test plan:
0. Don't apply this patch
1. Create a new patron with a streetnumber longer than 10 characters
2. Save
=> The patron has not been created and the app explodes
The error is about extended_attributes and not meaningful
Can't call method "extended_attributes" on an undefined value at /kohadevbox/koha/members/memberentry.pl line 560
3. Apply the patch
4. Repeat 1. and 2
=> You get a warning on the interface and you still see the creation
form
5. Check the logs
=> The error is meaningful
"Data too long for column 'streetnumber'"

Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>