Abort a play at the start when no hosts matches, or no hosts are remaining

This change makes a distinction between no_hosts_matched and no_hosts_remaining.

In both cases we do not start facts-gathering, or run any tasks.

In the case that there are no more hosts remaining, we abort running tasks and abort the playbook.

I also cleaned up the leftovers from the previous patchsets, as these are no longer required.

This closes #1187.

Example playbook:

```yaml
---
- hosts: emptygroup
  tasks:
  - action: command date
  - action: command false

- hosts: all
  gather_facts: False
  tasks:
  - action: command ls
  - action: command false
  - action: command true

- hosts: all
  tasks:
  - action: command true
  - action: command false

- hosts: all
  tasks:
  - action: command pwd
```

lib/ansible/callback_plugins/noop.py

@@ -63,6 +63,12 @@ class CallbackModule(object):
     def playbook_on_notify(self, host, handler):
         pass
 
+    def on_no_hosts_matched(self):
+        pass
+
+    def on_no_hosts_remaining(self):
+        pass
+
     def playbook_on_task_start(self, name, is_conditional):
         pass