[TUTO] Philomemy Notebook created with main functions to explorer the subject in collaboration with David.

       First select a period on Documents view.

       Then compute a graph chosing one distance (distributional or
       conditional).

       Then in Graph Explorer view (TinaWebJS), user can get colors of
       node with growth attributes.

       Red nodes are increasing.
       Yellow nodes are decreasing.

       Growth computed with previous period which is equal to the
       selected period in duration (but before).

       TODO: make some tests with Users to validate the fact that
       previous period is not all the corpus but the selected period.

[FEAT] Growth on graph: select a period in Documents view, compute a graph and user can get colors of node which are new compared with previous period which is equal the select period in duration (but before).

- Graphes asynchrones testés en mode prod
- Documentation, README amélioré
- cosmetics: aération du code (en particulier bridgeness...)
- factorisation et meilleur positionnement de la fonction compute_graph

 Modifications qui seront validées :
	modifié :         README.md
	modifié :         bridgeness.py
	modifié :         cooccurrences.py
	modifié :         graph.py

[GRAPH] Now graph as json is saved according to its distance as key (needs to add bridgeness parameter as key).

[GRAPH] Number of nodes need to be saved during the graph generation (and not only with cooc matrix); in order to keep all parameters.

- List cleaned
- Dynamic graph saved each time
- Removing page authors (for later)

- Map List Node id
- Group List Node id

- Start date (UTC format)
- End date (UTC format)

For now, this parameters should be added:
- distance (conditional or distributional)
- bridgeness

Need some refactoring to enable this.

[GRAPH EXPLORER] Better types to check parameters and give user some usefull informations. I extensively use the Either type of Haskell that is needed to easyly understand the logic of the process.