Remove Brunch setup for something better

[froi]

The brunch setup is kind of old and janky. We would like to change it to something more modern/easier/better. @jpadilla suggests webpack, but honestly I have no preference.

I would also no treat our static files as a app as it's handled now (maybe I'm wrong).

[gcollazo]

@froi que branch debería usar como punto de partida? master?

[froi]

Master.

[gcollazo]

Thanks