fix(Repository): LightLazy made obsolete.

At a later date we should remove it from code altogether.

Relates to #104.

Author: bavanade

src/Liquid.Repository/LightLazy.cs

@@ -4,6 +4,19 @@
 
 namespace Liquid.Repository
 {
+    /// <summary>
+    /// Specialization of a <see cref="Lazy{T}"/> that calls the valueFactory on a Task. 
+    /// </summary>
+    /// <typeparam name="T">The type of the object that is lazyly produced.</typeparam>
+    /// <remarks>
+    /// Made obsolete since there are issues with this type.
+    /// 
+    /// There's a conceptual issue here - lazy objects are be loaded at the last minute, when necessary. This
+    /// Lazy values are supposed to be loaded once, "just in time", and then available in memory. 
+    /// This implementation brings the extra effort of having to always await on a type that will 
+    /// almost always be available, which is a overhead that we should avoid. 
+    /// </remarks>
+    [Obsolete("Use System.Lazy instead.")]
     public class LightLazy<T> : Lazy<Task<T>>
     {
         public LightLazy(Func<T> valueFactory) : base(() => Task.Factory.StartNew(valueFactory))