Pontoon: Updated Spanish (es) localization of Pontoon Intro
Pontoon: Updated Spanish (es) localization of Pontoon Intro

Translation authors:
- Inma Barrios <inma.barrios@mozilla-hispano.org>

jotes/pontoon-intro,mathjazz/pontoon-intro,jotes/pontoon-intro,mathjazz/pontoon-intro,jotes/pontoon-intro,mathjazz/pontoon-intro