Bug 11127: OPAC suggestions form - complain when trying to 'delete selected' without having selected any

To reproduce:
1/ go on opac-suggestions.pl
2/ create a suggestion
3/ click on the delete link without checking any checkbox
The form is submitted with a message "The selected suggestions have been
deleted.".

Test plan:
0/ enable the bootstrap theme
1/ after applying the patch, click on delete without any checkbox
checked, a js alert should occur.
2/ check at least a cb and click on the delete link. The deletion should
work.

Followed test plan. Patch behaves as expected.
Signed-off-by: Marc Véron <veron@veron.ch>

Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
Passes all tests and QA script, works as described.

Signed-off-by: Galen Charlton <gmc@esilibrary.com>
Bug 11127: (follow-up) define a specific message for suggestions

Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
Signed-off-by: Galen Charlton <gmc@esilibrary.com>
Bug 11386: standardize validation of the subscription add/edit form

Use jQuery.validate plugin for subscription add/edit form and remove
readonly attribute on date fields, as datepicker is not available for
everyone.

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
Works as described, passes tests, and QA script.

Signed-off-by: Galen Charlton <gmc@esilibrary.com>