Created S# .sln and moved project to src folder

ICD.Common/Utils/Extensions/CollectionExtensions.cs

@@ -0,0 +1,47 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+
+namespace ICD.Common.Utils.Extensions
+{
+	/// <summary>
+	/// Extension methods for working with ICollections.
+	/// </summary>
+	public static class CollectionExtensions
+	{
+		/// <summary>
+		/// Removes items matching the predicate.
+		/// </summary>
+		/// <typeparam name="T"></typeparam>
+		/// <param name="extends"></param>
+		/// <param name="predicate"></param>
+		public static void RemoveAll<T>(this ICollection<T> extends, Func<T, bool> predicate)
+		{
+			if (extends == null)
+				throw new ArgumentNullException("extends");
+
+			if (predicate == null)
+				throw new ArgumentNullException("predicate");
+
+			extends.RemoveAll(extends.Where(predicate).ToArray());
+		}
+
+		/// <summary>
+		/// Removes all of the items from the other collection.
+		/// </summary>
+		/// <typeparam name="T"></typeparam>
+		/// <param name="extends"></param>
+		/// <param name="other"></param>
+		public static void RemoveAll<T>(this ICollection<T> extends, IEnumerable<T> other)
+		{
+			if (extends == null)
+				throw new ArgumentNullException("extends");
+
+			if (other == null)
+				throw new ArgumentNullException("other");
+
+			foreach (T item in other)
+				extends.Remove(item);
+		}
+	}
+}