First commit: project structure, ui, WIP ui logic

app/src/main/res/layout/number_picker_dialog.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:layout_gravity="center"
+    android:gravity="center_horizontal">
+
+    <NumberPicker
+        android:id="@+id/dialog_number_picker"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"/>
+</LinearLayout>