UI and UX on all pages

See merge request !9

# Conflicts:
#   routes/ads.js
#   views/ads/create.hbs

Images were overflowing out of parent, set their parent's width
to absolute value. REALLY WEIRD IM ANGRY AHHHH.

Testing (encore en cours mais on continuera sur master)

See merge request !8

refactor des tests pour ne plus utiliser la status
plus de status personnalisé sur redirections

Ajout gitignore la sortie des coverage stats
mort aux var

ajout d'un module de calcul de coverage

Gestion questions/réponses

Closes #6 et #7

See merge request !7

In update and show routes

Page was slown down because of this.

The styles of the messages will be specified by type of message :
- error
- success
- log (dev)
- info

The list is fully extensible, just have to write style
for class msg-TYPE and call flash with the given type.