Update the copyright coredits -- Happy new year 2013!

llvm-svn: 171342
diff --git a/lld/docs/conf.py b/lld/docs/conf.py
index 0657eb8..2518dad 100644
--- a/lld/docs/conf.py
+++ b/lld/docs/conf.py
@@ -40,7 +40,7 @@
 
 # General information about the project.
 project = u'lld'
-copyright = u'2012, LLVM Project'
+copyright = u'2011-2013, LLVM Project'
 
 # The version info for the project you're documenting, acts as replacement for
 # |version| and |release|, also used in various other places throughout the