use Regex.Replace instead of string.Replace

Author: siegfriedpammer

src/AddIns/DisplayBindings/AvalonEdit.AddIn/Src/ContextActions/ClipboardRingAction.cs

@@ -24,7 +24,7 @@ public class ClipboardRingAction : IContextAction
 
 		public ClipboardRingAction(string text) 
 		{
-			string entry = text.Trim().Replace('\t', ' ').Replace("\r\n", " ").Replace('\r', ' ').Replace('\n', ' ');
+			string entry = System.Text.RegularExpressions.Regex.Replace(text.Trim(), @"\s+", " ");
 			if(entry.Length > maxLength)
 				entry = entry.Substring(0, maxLength-endString.Length) + endString;