Use png for checker image to use it via bitmap

Signed-off-by: Unpublished <unpublished@gmx.net>

src/main/res/drawable/checker_16_16.xml

@@ -1,18 +0,0 @@
-<vector xmlns:android="http://schemas.android.com/apk/res/android"
-    android:width="16dp"
-    android:height="16dp"
-    android:viewportWidth="16"
-    android:viewportHeight="16">
-  <path
-      android:pathData="M-0.024,0.038l8.005,0l0,8.0003l-8.005,0z"
-      android:fillColor="#EBEBEB"/>
-  <path
-      android:pathData="M7.9998,8l8.005,0l0,8.0003l-8.005,0z"
-      android:fillColor="#EBEBEB"/>
-  <path
-      android:pathData="M7.9617,0.0142l8.005,0l0,8.0003l-8.005,0z"
-      android:fillColor="#ffffff"/>
-  <path
-      android:pathData="M-0.024,8l8.005,0l0,8.0003l-8.005,0z"
-      android:fillColor="#ffffff"/>
-</vector>