Add xml comments to IExecutionContext (graphql-dotnet#1598)

Author: Shane32

src/GraphQL/Execution/IExecutionContext.cs

@@ -9,30 +9,71 @@ namespace GraphQL.Execution
 {
     public interface IExecutionContext : IProvideUserContext
     {
+        /// <summary>
+        /// Propagates notification that the GraphQL request should be canceled
+        /// </summary>
         CancellationToken CancellationToken { get; }
 
+        /// <summary>
+        /// The parsed GraphQL request
+        /// </summary>
         Document Document { get; }
 
+        /// <summary>
+        /// A list of errors generated during GraphQL request processing
+        /// </summary>
         ExecutionErrors Errors { get; }
 
+        /// <summary>
+        /// A list of <see cref="FragmentDefinition"/>s that pertain to the GraphQL request
+        /// </summary>
         Fragments Fragments { get; }
 
+        /// <summary>
+        /// A list of <see cref="IDocumentExecutionListener"/>s, enabling code to be executed at various points during the processing of the GraphQL query
+        /// </summary>
         List<IDocumentExecutionListener> Listeners { get; }
 
+        /// <summary>
+        /// If set, limits the maximum number of nodes (in other words GraphQL fields) executed in parallel
+        /// </summary>
         int? MaxParallelExecutionCount { get; }
 
+        /// <summary>
+        /// Provides performance metrics logging capabilities
+        /// </summary>
         Metrics Metrics { get; }
 
+        /// <summary>
+        /// The GraphQL operation that is being executed
+        /// </summary>
         Operation Operation { get; }
 
+        /// <summary>
+        /// Object to pass to the <see cref="IResolveFieldContext.Source"/> property of first-level resolvers
+        /// </summary>
         object RootValue { get; }
 
+        /// <summary>
+        /// Schema of the graph to use
+        /// </summary>
         ISchema Schema { get; }
 
+        /// <summary>
+        /// When <c>false</c>, <see cref="DocumentExecuter"/> and <see cref="ExecutionStrategy"/> capture unhandled
+        /// exceptions and store them within <see cref="Errors">Errors</see>
+        /// </summary>
         bool ThrowOnUnhandledException { get; }
 
+        /// <summary>
+        /// A delegate that can override, hide, modify, or log unhandled exceptions before they are stored
+        /// within <see cref="Errors"/> as an <see cref="ExecutionError"/>.
+        /// </summary>
         Action<UnhandledExceptionContext> UnhandledExceptionDelegate { get; }
 
+        /// <summary>
+        /// Input variables to the GraphQL request
+        /// </summary>
         Variables Variables { get; }
     }
 }