[IMP] mrp: work orders planning

This PR introduce:
- State on kanban cards
- Do not allow a start date greater then a stop date.

The purpose and details are explain in each specific commit

Task ID -1838642
Pad - https://pad.odoo.com/p/r.68c799c9a80a18157eefebc39452f311

closes odoo/odoo#25103

addons/mrp/models/mrp_workorder.py

@@ -64,7 +64,7 @@ class MrpWorkorder(models.Model):
         compute='_compute_is_produced')
 
     state = fields.Selection([
-        ('pending', 'Pending'),
+        ('pending', 'Waiting for another WO'),
         ('ready', 'Ready'),
         ('progress', 'In Progress'),
         ('done', 'Finished'),
@@ -230,8 +230,14 @@ class MrpWorkorder(models.Model):
 
     @api.multi
     def write(self, values):
-        if ('date_planned_start' in values or 'date_planned_finished' in values) and any(workorder.state == 'done' for workorder in self):
+        if list(values.keys()) != ['time_ids'] and any(workorder.state == 'done' for workorder in self):
             raise UserError(_('You can not change the finished work order.'))
+        if 'date_planned_start' in values or 'date_planned_finished' in values:
+            for workorder in self:
+                start_date = fields.Datetime.to_datetime(values.get('date_planned_start')) or workorder.date_planned_start
+                end_date = fields.Datetime.to_datetime(values.get('date_planned_finished')) or workorder.date_planned_finished
+                if start_date and end_date and start_date > end_date:
+                    raise UserError(_('The planned end date of the work order cannot be prior to the planned start date, please correct this to save the work order.'))
         return super(MrpWorkorder, self).write(values)
 
     def _generate_lot_ids(self):

addons/mrp/views/mrp_workorder_views.xml

@@ -358,10 +358,13 @@
                     <t t-name="kanban-box">
                         <div t-attf-class="oe_kanban_card oe_kanban_global_click">
                             <div class="oe_kanban_content">
-                                <div>
-                                    <strong class="o_kanban_record_title">
+                                <div class="o_kanban_record_top">
+                                    <strong class="o_kanban_record_headings">
                                         <span><t t-esc="record.production_id.value"/></span> - <span><t t-esc="record.name.value"/></span>
                                     </strong>
+                                    <span t-attf-class="badge #{['pending'].indexOf(record.state.raw_value) > -1 ? 'badge-warning' :['progress'].indexOf(record.state.raw_value) > -1 ? 'badge-secondary' : ['ready'].indexOf(record.state.raw_value) > -1 ? 'badge-primary' : ['done'].indexOf(record.state.raw_value) > -1 ? 'badge-success' : 'badge-danger'}">
+                                        <t t-esc="record.state.value"/>
+                                    </span>
                                 </div>
                                 <div class="o_kanban_record_bottom">
                                     <div class="oe_kanban_bottom_left">