Add comment about unimplemented line continuation support

Author: rjmholt

src/PowerShellEditorServices/Services/PowerShell/Console/LegacyReadLine.cs

@@ -8,14 +8,13 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.Management.Automation;
-using System.Management.Automation.Language;
 using System.Text;
 using System.Threading;
+using System.Threading.Tasks;
 
 namespace Microsoft.PowerShell.EditorServices.Services.PowerShell.Console
 {
     using System;
-    using System.Threading.Tasks;
 
     internal class LegacyReadLine : TerminalReadLine
     {
@@ -331,6 +330,10 @@ public override string ReadLine(CancellationToken cancellationToken)
                             currentCompletion = null;
                             currentHistory = null;
 
+                            // TODO: Add line continuation support:
+                            // - When shift+enter is pressed, or
+                            // - When the parse indicates incomplete input
+
                             //if ((keyInfo.Modifiers & ConsoleModifiers.Shift) == ConsoleModifiers.Shift)
                             //{
                             //    // TODO: Start a new line!