add resource.py file missed on last commit

resource.py

@@ -0,0 +1,25 @@
+from trytond.pool import Pool, PoolMeta
+
+__all__ = ['ResourceBooking']
+__metaclass__ = PoolMeta
+
+
+class ResourceBooking:
+    __name__ = 'resource.booking'
+
+    @classmethod
+    def confirm(cls, bookings):
+        pool = Pool()
+        Work = pool.get('project.work')
+        super(ResourceBooking, cls).confirm(bookings)
+        to_write = []
+        for booking in bookings:
+            work = booking.document
+            if (work and isinstance(work, Work) and not work.assigned_employee
+                    and booking.resource.employee):
+                to_write.extend(([work], {
+                            'assigned_employee': booking.resource.employee.id,
+                            }))
+
+        if to_write:
+            Work.write(*to_write)