Bug 10865: (Follow-up) Add CSS style for form hints

Bug 10865: (Follow-up) Add CSS style for form hints

This patch adds a new "hint" class for displaying information relating
to a form field. On the list edit screen the hint also has an alert
class to highlight it.

Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
Passes all tests and QA script. Works as advertised.
Tested with Bootstrap and prog theme. Some notes:

- When OpacAllowPublicListCreation is turned off, the permissions
  don't show.
- When OpacAllowPublicListCreation is turned off, we could also hide
  the Category pull down in the [new list] pop up, as there is only
  Private left as an option.
- Maybe we should move the new list link outside of the tabs?
  When OpacAllowPublicListCreation is turned off, but public lists
  exist, the link 'new list' will still show on the public list tab,
  but a private list will be created.

Signed-off-by: Galen Charlton <gmc@esilibrary.com>
(cherry picked from commit 9094b4a1bbff95e0f8e5747a805dacede165bc9a)
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>
Conflicts:
	koha-tmpl/opac-tmpl/bootstrap/css/opac.css