Add pizzigati prize blog post

pages/about-us/news/2018/pizzigati-price.md

+@title = 'LEAP member received the 2018 Pizzigati Prize'
+@author = 'isydor'
+@posted_at = '2018-05-03'
+@more = false
+@preview_image = '/img/pages/tides_logo.png'
+
+We are proud that [Tides](https://www.tides.org/) awarded LEAP
+member Andre Bianchi the [2018 Pizzigati
+Prize](https://www.tides.org/accelerating-social-change/2018-pizzigati-prize-andre-bianchi/). Thank you a lot for this recognition of the work done to make it
+possible to freely communicate digitally and to support social change!