Add boilerplate for root project

src/main/java/com/cleverthis/interview/Solution.java

@@ -0,0 +1,14 @@
+package com.cleverthis.interview;
+
+import com.cleverthis.interview.padlock.PadlockImpl;
+import sun.reflect.generics.reflectiveObjects.NotImplementedException;
+
+/**
+ * This is a placeholder class showing a simple boilerplate.
+ * This class is not required, so you can replace with your own architecture.
+ * */
+public class Solution {
+    public void solve(PadlockImpl padlock) {
+        throw new RuntimeException("TODO");
+    }
+}