Logging

[rubensworks]

We should support logging like in the old ldf-client, for logging things like the executed HTTP requests. This is required for comunica/jQuery-Widget.js#2.

Potentially related to #109.

[rubensworks]

While the comunica prototype initially uses a winston logger, it felt too limited, so I suggest not using it again.

I think a more configurable logging framework (like log4js) would be ideal, as it supports different logging levels and categories.

One thing to keep in mind is performance. So we might want to scope logging calls behind certain flags.

[rubensworks]

This might be a good lib we can use: https://github.com/guigrpa/storyboard

[rubensworks]

Depends on #109.

[rubensworks]

Two types of logging are needed: Intra and inter-actor logging.

[rubensworks]

As of #183, contexts are now passed along all IAction's, so this can be implemented with this.

[rubensworks]

Bunyan seems to be good and flexible enough for our case, and there also exists an isomorphic version (https://www.npmjs.com/package/iso-bunyan-stream).

#204 has to be fixed before this can be implemented, as the initialize methods seems to be the best way to pass around logger instances. (I want to avoid static solutions)