[CRM] crm: activities improvements

When you change the activity on the Schedule activity wizard, keep the scheduled date

Rename a string on dashboard

addons/crm/wizard/crm_activity_log.py

@@ -38,7 +38,6 @@ class ActivityLog(models.TransientModel):
     def onchange_next_activity_id(self):
         if not self.title_action:
             self.title_action = self.next_activity_id.description
-        date_action = False
         if self.next_activity_id and self.next_activity_id.days:
             date_action = (datetime.now() + timedelta(days=self.next_activity_id.days)).strftime(tools.DEFAULT_SERVER_DATETIME_FORMAT)
         self.date_action = date_action

addons/sales_team/static/src/xml/sales_team_dashboard.xml

@@ -212,7 +212,7 @@
                 <div class="o_welcome_content">
                     <h2>Hi there!</h2>
                     <h4>Great sales journeys start with a clean pipeline.</h4>
-                    <h4>Create a few opportunities to activate your dashboard.</h4>
+                    <h4>Create a few opportunities in it.</h4>
                     <a class="btn btn-primary o_dashboard_action" name="crm.action_your_pipeline">My Pipeline</a>
                 </div>
             </div>