Update copyright headers

Author: pavel-alay

itext/itext.io/itext/io/util/IanaEncodings.cs

@@ -5,7 +5,7 @@
  * 
  *
  * This file is part of the iText project.
- * Copyright (c) 1998-2017 iText Group NV
+ * Copyright (c) 1998-2018 iText Group NV
  * Authors: Bruno Lowagie, Paulo Soares, et al.
  *
  * This program is free software; you can redistribute it and/or modify

itext/itext.kernel/itext/kernel/Version.cs

@@ -84,7 +84,7 @@ public sealed class Version {
         /// iText Group requests that you retain the iText producer line
         /// in every PDF that is created or manipulated using iText.
         /// </remarks>
-        private String producerLine = iTextProductName + " " + release + " \u00a92000-2017 iText Group NV";
+        private String producerLine = iTextProductName + " " + release + " \u00a92000-2018 iText Group NV";
 
         /// <summary>The license key.</summary>
         private String key = null;

itext7.nuspec

@@ -13,7 +13,7 @@
     <description>iText 7 represents the next level of SDKs for developers that want to take advantage of the benefits PDF can bring. Equipped with a better document engine, high- and low-level programming capabilities and the ability to create, edit and enhance PDF documents, iText 7 can be a boon to nearly every workflow. iText 7 allows you to build custom PDF scenarios for web, mobile, desktop or cloud apps in Java and .NET.</description>
     <summary>iText for .NET is a port of the iText open source java library for PDF generation written entirely in C# for the .NET platform.</summary>
     <releaseNotes>http://itextpdf.com/itext7release</releaseNotes>
-    <copyright>Copyright (c) 1998-2017 iText Group NV</copyright>
+    <copyright>Copyright (c) 1998-2018 iText Group NV</copyright>
     <language>en-US</language>
     <tags>itext itext7 itextsharp c# .net csharp pdf</tags>
     <dependencies>