Added test for primes list.

Author: n.bitounis

UnitTest/AlgorithmsTests/PrimeListTest.cs

@@ -0,0 +1,15 @@
+using DataStructures.Common;
+using Xunit;
+
+namespace UnitTest.AlgorithmsTests
+{
+    public class PrimeListTest
+    {
+        [Fact]
+        public void DoTest()
+        {
+            var instance = PrimesList.Instance;
+            Assert.Equal(10000, instance.Count);
+        }
+    }
+}