Moved all UnitTests to a single project. Implemented parts of AspNetCore UnitTests.

UnitTests/Common/Utils/CustomMultipleAttribute.cs

@@ -0,0 +1,16 @@
+using System;
+
+namespace UnitTests.Common.Utils
+{
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
+	[AttributeUsage(AttributeTargets.All, AllowMultiple = true)]
+	internal class CustomMultipleAttribute : Attribute
+	{
+		public CustomMultipleAttribute(string name)
+		{
+			Name = name;
+		}
+
+		public string Name { get; set; }
+	}
+}