Move the test library sources to src/, and compile a real lib for the test and

perf programs to use.

src/characters.cpp

@@ -0,0 +1,8 @@
+/**
+ *   Copyright (C) 2017 Zach Laine
+ *
+ *   Distributed under the Boost Software License, Version 1.0. (See accompanying
+ *   file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+ */
+
+#include <yaml/parser/characters_def.hpp>