Created HandOfCards class, created method to check for flush

src/main/java/edu/ntnu/idatt2003/HandOfCards.java

+package edu.ntnu.idatt2003;
+
+import java.util.List;
+
+public class HandOfCards {
+    private List<PlayingCard> hand;
+
+    public HandOfCards(List<PlayingCard> hand) {
+        this.hand = hand;
+    }
+
+    public boolean isFlush() {
+        if (hand.size() < 5) {
+            return false;
+        }
+
+        return false;
+    }
+}