Bump version to 15.0.0

Signed-off-by: Tim Krüger <t@timkrueger.me>

app/build.gradle

@@ -45,8 +45,8 @@ android {
 
         // mayor.minor.hotfix.increment (for increment: 01-50=Alpha / 51-89=RC / 90-99=stable)
         // xx   .xxx  .xx    .xx
-        versionCode 140020006
-        versionName "14.2.0 Alpha 06"
+        versionCode 150000001
+        versionName "15.0.0 Alpha 01"
 
         flavorDimensions "default"
         renderscriptTargetApi 19