Capacité à uploader un fichier pour les configurations

[PonteIneptique]

Idées

L'upload de fichier vers le serveur semble complètement inutile et pourrait provoquer une surchage à gérer. Par contre, on peut utiliser jQuery/Javascript pour lire le contenu d'un fichier et remplir les textarea :)

Ressources :

• https://www.html5rocks.com/en/tutorials/file/dndfiles/
• https://stackoverflow.com/questions/12281775/get-data-from-file-input-in-jquery

Actual behaviour

First situation

1. As a normal user, when I create a corpus
2. Click New Corpus
3. Click on Write your own to show the control list creation as well
4. Fields #tokens and #allowed_lemma, #allowed_POS and #allowed_morph need to received huge amount of data, most of the time they are copy pasted

Second situation

1. As a control list administrator, when I want to edit a control list,
2. Click on Control List > Any control list you contorl.
3. On the home page of the control list, 3 yellow buttons are visible, they all start with rewrite
4. On their page, a single field need to received huge amount of data, most of the time they are copy pasted

Expected Behaviour

Add a button so that

1. User can click upload file
2. The file is read client side and inserted in the text area.

[PonteIneptique]

There is a very simple yet working (I think) implementation of this in the following branch : a129625

[carinedengler]

We estimate this ticket to take us 2d.