bump version to 80

Change-Id: Id4c05a03574a07c4b16766c7575068c69452613f

ring-android/app/src/main/AndroidManifest.xml

@@ -20,7 +20,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
     package="cx.ring"
     android:installLocation="auto"
-    android:versionCode="79"
+    android:versionCode="80"
     android:versionName="20170531">
 
     <supports-screens