Pontoon: Updated Polish (pl) localization of Pontoon Intro
Pontoon: Updated Polish (pl) localization of Pontoon Intro

Translation authors:
- mdziewonski <mdziewonski@mozilla.com>

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