Update missed files for 2017

.nb-gradle/licenseheader.txt

@@ -1,7 +1,7 @@
 <#if licenseFirst??>
 ${licenseFirst}
 </#if>
-${licensePrefix}Copyright (c) 2006-2015 DMDirc Developers
+${licensePrefix}Copyright (c) 2006-2017 DMDirc Developers
 ${licensePrefix}
 ${licensePrefix}Permission is hereby granted, free of charge, to any person obtaining a copy
 ${licensePrefix}of this software and associated documentation files (the "Software"), to deal

LICENCE

@@ -1,4 +1,4 @@
-Copyright (c) 2006-2015 DMDirc Developers
+Copyright (c) 2006-2017 DMDirc Developers
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal