vmhost: add status field

uncloud/uncloud_vm/models.py

@@ -17,6 +17,16 @@ class VMHost(models.Model):
     usable_ram_in_gb = models.FloatField()
 
 
+    status = models.CharField(max_length=32,
+                              choices = (
+                                  ('pending', 'Pending'),
+                                  ('active', 'Active'),
+                                  ('unusable', 'Unusable'),
+                              ),
+                              default='pending'
+    )
+
+
 class VM(models.Model):
     uuid = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
     owner = models.ForeignKey(get_user_model(), on_delete=models.CASCADE)