Basic installation

Creation of html elements in index, and link to the bubble loader in
app.scss
Animation completed, a few ajustments within the index.html to make it less complex
Just cleaning
Fix blink

Ending animation was blinking, just fixing it by making the border
visible, and the content transparent.
Fix duration
Merge pull request #1 from Solatrix/loader-bubbles

Ajout d'un loader en bulle