Client notifies server when ending

See merge request !41

Server now exposes a callback for the client to notifies it when finished. This
allows the server to clean up the registry.

Careful, this introduces #65 when debugging.

Resolve "Check mocking framework"

Closes #54

See merge request !42

add sinon to 'live-reco-test.js' to mock XMLHttpRequest
delete console.logs from tests

add server disconnect function

Closes #59

See merge request !40

Add server-side controller with client registry

See merge request !39

The server controller now check that there is no client registered for the given
room before creating one.

Since it handles client creation, the controller now manager the registry.

Add corresponding tests.

The (currently very basic) client creation logic is now into a
dedicated (actual) `controller` module.

This will allow for cleaner dev and (especially) tests.

Server-side module `controller` used a confusing name not actually reflecting
its purpose. Rename it to the more accurate `loader` name.

This will allows to easily create multiple clients later.

First step to handle multiple, non-conflicting clients connecting to different
rooms.

`xo` was the only package not to be fixed to an exact version. Fix (hoho) this.

yarn.lock update was long overdue. Some old dependencies were not removed.

Dockerfile: replace ENTRYPOINT by CMD

See merge request !38

Make it easier to override the default command.

Dockerfile: add yarn.lock before running `yarn install`

Closes #61

See merge request !37

fix #61

update dockerignore and gitignore

Closes #60

See merge request !36

`models` should not be versioned or added to the container
added a lot of useless files to .dockerignore

fix #60

Hublot sbenhamiche#33

Closes #33

See merge request !35

Issue 55 - Manage reconnection

Allow the bot to reconnect to a conference with a proper initialisation
state

Closes #56

See merge request !34

Add LICENSE file and headers

Closes #49

See merge request !33

fix #49