Added minimal docs on the projectable attribute

src/EntityFrameworkCore.Projectables.Abstractions/ProjectableAttribute.cs

@@ -6,9 +6,15 @@ using System.Threading.Tasks;
 
 namespace EntityFrameworkCore.Projectables
 {
+    /// <summary>
+    /// Mark this method or property as a Projectable
+    /// </summary>
     [AttributeUsage(AttributeTargets.Method | AttributeTargets.Property, Inherited = true, AllowMultiple = false)]
     public sealed class ProjectableAttribute : Attribute
     {
+        /// <summary>
+        /// Get or set how null-conditional operators are handeled
+        /// </summary>
         public NullConditionalRewriteSupport NullConditionalRewriteSupport { get; set; }
     }
 }