Fix Lexicon constructor.

libwccl/lexicon/lexicon.h

@@ -16,7 +16,7 @@ public:
 
 	Lexicon(const std::string& name, const std::string& file_name)
 		: name_(name),
-		  file_name_(file_name_)
+		  file_name_(file_name)
 	{
 		BOOST_ASSERT(!name_.empty());
 	}