- Y axis : according to 12 hour or 24 hour format
- Event title : following time format in preferenced language
NB: The conversion from 'A' to 'TT' to match fullcalendar v1 should be
removed when fullcalendar is updated to v2, as the syntax will change.
See : http://fullcalendar.io/wiki/Upgrading-to-v2/
Backport of commit c1d813ec1c
opw-704237