[LyX/master] preserve symlinks on copying of user directory from previous version

[Stephan Witt]

commit 92b08869b2403b4091e7081e1001a33fd5f9c68b
Author: Stephan Witt <sw...@lyx.org>
Date:   Wed Jul 22 06:37:52 2015 +0200

    preserve symlinks on copying of user directory from previous version

diff --git a/lib/configure.py b/lib/configure.py
index 93ed5fd..1554ee5 100644
--- a/lib/configure.py
+++ b/lib/configure.py
@@ -166,7 +166,7 @@ def checkUpgrade():
             logger.debug('previous = ' + previous)
             if os.path.isdir( previous ):
                 logger.info('Found directory "%s".', previous)
-                copy_tree( previous, cwd )
+                copy_tree( previous, cwd, true )
                 logger.info('Content copied to directory "%s".', cwd)
                 return