Doxygen-related changes and minor code modifications
diff --git a/test/test_digest.cc b/test/test_digest.cc
index cbbc385..f942779 100644
--- a/test/test_digest.cc
+++ b/test/test_digest.cc
@@ -30,6 +30,7 @@
 #include <sstream>
 
 using namespace Sync;
+using namespace Sync::Error;
 using namespace std;
 using namespace boost;