Document how we ship embedded PHP libraries now.

Signed-off-by: Michal Čihař <michal@cihar.com>

doc/copyright.rst

@@ -6,7 +6,7 @@ Copyright
 .. code-block:: none
 
     Copyright (C) 1998-2000 Tobias Ratschiller <tobias_at_ratschiller.com>
-    Copyright (C) 2001-2014 Marc Delisle <marc_at_infomarc.info>
+    Copyright (C) 2001-2016 Marc Delisle <marc_at_infomarc.info>
         Olivier Müller <om_at_omnis.ch>
         Robin Johnson <robbat2_at_users.sourceforge.net>
         Alexander M. Turek <me_at_derrabus.de>
@@ -39,12 +39,5 @@ jQuery's license, which is where we got the files under js/jquery/ is
 (MIT|GPL), a copy of each license is available in this repository (GPL
 is available as LICENSE, MIT as js/jquery/MIT-LICENSE.txt).
 
-TCPDF which is located under libraries/tcpdf is released under GPL
-version 3 and the license is available as libraries/tcpdf/LICENSE.TXT.
-
-DejaVu fonts which are located under libraries/tcpdf/fonts/ and their
-license is documented in
-libraries/tcpdf/fonts/dejavu-fonts-ttf-2.33/LICENSE.
-
-PHP-gettext which is located under libraries/php-gettext/ is released
-under GPL version 2 license which is available in the LICENSE file.
+The download kit additionally includes several composer libraries. See their
+licensing information in the vendor/ directory.

doc/vendors.rst

@@ -27,9 +27,6 @@ Currently known list of external libraries:
 js/jquery
     jQuery js framework and various jQuery based libraries.
 
-libraries/php-gettext
-    php-gettext library
-libraries/tcpdf
-    tcpdf library, stripped down of not needed files
-libraries/phpseclib
-    portions of phpseclib library
+vendor/
+    The download kit includes various Composer packages as 
+    dependencies.