Add implementation of the generic pype daemon.
It's implementation is split into `daemon.py` where we implement an
http framework agnostic interface, and `app.py` that uses it to serve
them using starlette.
Now pype has an `autocomplete` command usable to enable autocompletion
and revng2 now is based on `pype`, modifying its defalults and
injecting new commands.
Now the model has a mime_type that we expect to return to the UI, and
model_name so the name of the model on disk can be impl-specific.
Moreover, now Model and Container use the same logic to detect if
a mimetype is textual.
Change the signature of `Container.serialize` and
`Container.deserialize` to use `Buffer` instead of `bytes`, as this
makes the functions compatible with the `revng::pypeline::Buffer`
classes.
Giacomo Vercesi