[IMP] hr_*: introduce the employee profile

General Purpose
===============

We want an 'Employee profile' gathering every data about an employee.
The main form view is modified to become this employee profile.
A user can also see his own profile through the Preferences menu.
The new profile replaces the current Preferences view if the hr module is installed
and the current user is linked to an employee.

A user should be able to see and edit his own profile.

*Problem*:
Many fields on hr.employee are protected by groups="hr.group_hr_user".
Therefore, a regular user cannot see or edit those fields.

This protection must be bypassed to allow read/write access
to the regular user's own data.
A similar mechanism already exists for res.users (for Preferences)

The better (least worst) solution found is to reuse this mechanism by adding related fields on res.users.

Pros:
- Don't change security access on hr.employee
- Don't implement yet another custom security layer, risking to add new security breaches
- A lot of fields are added by other modules on hr.employee.
  It would have required to integrate them with the custom security layer.
- Fields added by other modules on the user's preferences view (normal view, not the profile)
  are automatically included in the employee's profile view.
- Allow the hr.employee form view to be different than the user profile accessible
  through the Preferences menu.
  E.g. add custom buttons only relevant to the logged in user such as "Request a leave".
Cons:
- Each field from hr.employee that you want to appear on its profile
  must be added as a related field on res.users
- Those related fields must be added to user's preferences view (duplicate views)
- They also must be added to SELF_[READABLE | WRITABLE]_FIELDS

Note:
When the front-end loads the views it gets the list of available fields
for the user (according to its access rights). Later, when the front-end wants to
populate the view with data, it only asks to read those available fields.
However, in this case, we want the user to be able to read/write its own data,
even if they are protected by groups (groups are kept on the related fields on res.users).
The front-end need to be made  aware of those fields by sending all field definitions.

hr_attendance
=============

This commit integrate attendance in the new employee profile.
It also adds a stat button to this employee profile showing
the number of hours worked last month.

Remove the boolean computed field 'manual_attendance'.
This field is just a shortcut to add/remove the employee's user
in the "Manual Attendance" group.
The checkbox is confusing on the employee's form and this should
be done through the normal group management screens.

hr_presence
===========

Display the presence status on the employee kanban template.
The status is a colored chip which can be green (present),
orange (to define) or red (absent).

Currently, the presence status is only computed when accessing
the report view. As this commits displays it on the employee kanban,
it should be updated more frequently.
The state should not be updated every time the kanban view is loaded
since the computation is a bit heavy. Instead: add a cron to update
status every 15 minutes.
-> The status is accurate on the report view (status is still updated
   when loading the view)
-> The status in accurate at 15 minutes on the kanban view

[ADD] hr_attendance_presence
============================

Bridge module between hr_attendance and hr_presence.

This commit integrates hr_presence module in the employee
profile and adds the presence status on the employee kanban view.
But hr_attendance adds at the same place a similar status icon for
checkin/checkout.
This bridge module makes the status from hr_presence invisible as
hr_attendance should be the main presence control mechanism.

Also, this commit adds the ability (through a new setting option)
for hr_presence to take into account checkin/checkout to determine
the presence status.

l10n_be_hr_payroll
==================
integration with employee profile