Add a new overload to accept a string as an owner password

Author: VahidN

src/iTextSharp.LGPLv2.Core/iTextSharp/text/pdf/PdfReader.cs

@@ -143,7 +143,7 @@ public class PdfReader : IPdfViewerPreferences, IDisposable
     ///     @throws IOException on error
     /// </summary>
     /// <param name="filename">the file name of the document</param>
-    public PdfReader(string filename) : this(filename, ownerPassword: null)
+    public PdfReader(string filename) : this(filename, (byte[])null)
     {
     }
 
@@ -160,6 +160,16 @@ public PdfReader(string filename, byte[] ownerPassword)
         ReadPdf();
     }
 
+    /// <summary>
+    ///     Reads and parses a PDF document.
+    ///     @throws IOException on error
+    /// </summary>
+    /// <param name="filename">the file name of the document</param>
+    /// <param name="ownerPassword">the password to read the document</param>
+    public PdfReader(string filename, string ownerPassword) : this(filename, ownerPassword.GetIsoBytes())
+    {
+    }
+
     /// <summary>
     ///     Reads and parses a PDF document.
     ///     @throws IOException on error