Bug 5031: CSV profiles: validate required content fields

Bug 5031: CSV profiles: validate required content fields

Some fields are required on editing/adding CSV profiles.  This
patch adds HTML5 validation so that required fields must be
filled in before the form is submitted.

Test plan:
- add a new CSV profile (tools/csv-profiles.pl) without any value.
- save => error on empty fields.
- fill the "marc" content, select type="sql", fill the CSV name input.
- save => error on sql content field.
- fill the sql content
- save => the CSV profile is saved.
- retry for the edit form.

Signed-off-by: Bernardo Gonzalez Kriegel <bgkriegel@gmail.com>
Comment: On top of both patches for Bug 10853

Works very well, now we get an alert with empty field
Saves correctly MARC and SQL profiles

Solved minor conflict introduced by tab followup on Bug 10853
Again small tab errors corrected in followup

Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
Works as described, looks a bit 'non standard' for Koha,
but improves usability of the form.

Signed-off-by: Galen Charlton <gmc@esilibrary.com>
(cherry picked from commit 8c5278270708724808b3585dc798e9300abeed31)
Signed-off-by: Fridolin SOMERS <fridolin.somers@biblibre.com>