Added markdown to deck descriptions.
Added Chart.js to dependencies
Added django debug toolbar
Fix a bug in debug toolbar.

For some reason, django debug toolbar was not working properly, probably
because of some change in the settings. Fortunately, it was an easy fix.
Added debug toolbar settings
Added charts to the deck view.

I also had to move the converted_mana function to a single field, was
really easier to do it so.
Fixed a bug with card count.

The cards were badly counted to do the stats : we counted the number of
different cards, but forgot to take into account the quantity of each
cards. Fixed now.
Warns the user that registration is not possible yet.