Created S# .sln and moved project to src folder

ICD.Common/Attributes/AbstractIcdAttribute.cs

@@ -0,0 +1,40 @@
+using System;
+
+namespace ICD.Common.Attributes
+{
+	/// <summary>
+	/// AbstractIcdAttribute is the base class for all ICD attributes.
+	/// It provides a global cache for looking up symbols via an attribute type.
+	/// </summary>
+	public abstract class AbstractIcdAttribute : Attribute
+	{
+		private readonly int m_HashCode;
+
+		#region Constructors
+
+		/// <summary>
+		/// Constructor.
+		/// </summary>
+		protected AbstractIcdAttribute()
+		{
+			// Duplicate attributes (E.g. [A, A]) are considered to be the same instance by reflection.
+			// We get around this by using a GUID for the hash code.
+			m_HashCode = Guid.NewGuid().GetHashCode();
+		}
+
+		#endregion
+
+		#region Methods
+
+		/// <summary>
+		/// Gets the hash code for the instance.
+		/// </summary>
+		/// <returns></returns>
+		public override int GetHashCode()
+		{
+			return m_HashCode;
+		}
+
+		#endregion
+	}
+}