Added splash screen. Minor refactoring.

app/src/main/res/drawable/splash_drawable.xml

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="utf-8"?>
+<layer-list xmlns:android="http://schemas.android.com/apk/res/android"
+    android:opacity="opaque">
+    <item android:drawable="@color/darkOnLight" />
+    <item
+        android:width="240dp"
+        android:height="240dp"
+        android:drawable="@drawable/splash_foreground"
+        android:gravity="center" />
+</layer-list>