added new hooks

[volkan]

No description provided.

[thp]

Please do not check in the *.pyc bytecode files.

[thp]

Also, please provide a description what your change does and what the goal of the change is - i.e. what use cases there are for using those features that you add.

[volkan]

Sorry for pyc files. I fixed it.

1.diff_after_hook which is used when the difference appears. For cache invalidation like varnish or other tools.
2.request_hook is used to customize main request or to add the process of a new request. Like login process.

[thp]

For the "PURGE" (request hook) requests, maybe that could be a new job type after #32 has been merged? Also, on top of #32 we could probably make the hooks a bit nicer in general (or also make a login job type that then calls some hooks).

[volkan]

It sounds good.

[thp]

These changes have now been merged. For a simple change in HTTP method, you can now just specify method: PURGE in the YAML file. For logins, you can define a new job type that handles the login. I have added corresponding examples to urls.yaml.example and hooks.py.example.