[IMP] hr_holidays: also calculates virutal remaining leaves
[IMP] hr_holidays: cleaning + improve check_holidays
[IMP] hr_holidays: workflow update
starts in confirm
from confirm, possible to get back to draft with reset signal, calling old set_to_draft, now
renamed holidays_reset, in the same workflow
from draft, possible to go to confirm
[MERGE] Sync with trunk
[IMP] hr_holidays:
- added a workflow transition from refuse to draft, to allow resetting
a refused request
- resetting is now based on a can_reset field, taht is based on whether
it is my own request or I am an hr manager
- added an access right on crm_meeting that was preventing hr officers
to validate some requests
- improved form view to show reset to draft button accordingly
- added tests that helped trigerred the various bugs and improvements
[DOC] hr_holidays: added basic changelog
[IMP] hr_holidays: leave summary: removed default filter default_validated, but added a domain to exclude refused requests from the summary. This was creating wrong numbers that do not make any sense.
[MERGE] Sync with trunk
[MERGE] [IMP] hr_holidays: days computation and workflow update

Remaining days calculation:
- get_days now also calculate virtual remaining days that take into account the confirmed leave requests.
- virtual remaining days are taken into account when confirming / validating a leave request. This allows to avoid having several pending leave requests that cannot be validated because of a lack of remaining days once all requests are validated.

Workflow update:
- begins in confirm state
- added transition confirm->draft; transition draft->confirm is not automatic anymore (Confirm button)
- added transition refuse->draft, to reset the leave request and allow edition

Misc
- leave summary does not show refused leave requests anymore
- added tests + some fixes for bugs trigerred by the tests (mainly access rights issues)
- added changelog