Jupyter Backend

[boisgera]

TODO:

• Solve missing imports
• Map to GFM (e.g. to get the proper map support)
• Internal links (generate dummy ids/span)
• Typography : "--"
• Color backgrounds ? (Not sure it's possible; not unless we convert the whole block to HTML?)
• Need to normalize the size of images and drop the special attributes that are not rendered (?)
• Support for videos.
• Can't split code in multiple cells once figure() appears