Doxygen-related changes and minor code modifications
diff --git a/model/sync-diff-leaf.cc b/model/sync-diff-leaf.cc
index 0790ec7..d2b7d7f 100644
--- a/model/sync-diff-leaf.cc
+++ b/model/sync-diff-leaf.cc
@@ -24,6 +24,8 @@
 #include <boost/throw_exception.hpp>
 typedef boost::error_info<struct tag_errmsg, std::string> errmsg_info; 
 
+using namespace Sync::Error;
+
 namespace Sync {
 
 DiffLeaf::DiffLeaf (NameInfoConstPtr info, const SeqNo &seq)