Add language headers

Author: marcprux

index-de.md

@@ -1,6 +1,7 @@
 ---
 layout: page
 title: "Keep Android Open"
+lang: de
 permalink: /de/
 description: "Befürwortung von Android als kostenlose und offene Plattform für jeden, um Apps zu entwickeln."
 

index-fr.md

@@ -1,6 +1,7 @@
 ---
 layout: page
 title: "Keep Android Open"
+lang: fr
 permalink: /fr/
 description: "Plaidoyer pour Android en tant que plateforme libre et ouverte permettant à tous de développer des applications."
 

index-tr.md

@@ -1,6 +1,7 @@
 ---
 layout: page
 title: "Android Açık Kalsın"
+lang: tr
 permalink: /tr/
 description: "Android'in herkesin üzerinde uygulama geliştirebileceği özgür, açık bir platform olmasını savunuyoruz."
 

index.md

@@ -1,6 +1,7 @@
 ---
 layout: page
 title: "Keep Android Open"
+lang: en
 permalink: /
 description: "Advocating for Android as a free, open platform for everyone to build apps on."