[IMP] hr_holidays: Add leave stats widget

When approving a leave, to make an informed decision, it might
be needed to check leaves already taken by the employee or leaves
of its collaborators. This commit adds a widget displaying some stats
in a leave form view. Stats displayed are:
   - the number of days taken
   by the employee this year, grouped by leave type
   - Leaves taken by employees in the same department in the month
   of the leave.
This widget is only displayed in the context of the action leading
to leaves to approve.

0 files changed, 0 insertions, 0 deletions