Initial release of the Achievement System (#2044)

* Information based on kRO patch notes.
- http://ro.gnjoy.com/news/update/View.asp?seq=163&curpage=1
* Includes Title System which is integrated into the Achievement System.
* Includes RODEX integration for rewards.
* Added new atcommand reloadachievementdb.
* Added new script commands achievementinfo, achievementadd, achievementremove, achievementcomplete, and achievementexists.
Thanks to @Lux-uri, @RagnarokNova, @Lemongrass3110, and @Tokeiburu for their help!

3rdparty/yaml-cpp/src/singledocparser.cpp

@@ -166,10 +166,10 @@ void SingleDocParser::HandleBlockSequence(EventHandler& eventHandler) {
 
     // check for null
     if (!m_scanner.empty()) {
-      const Token& token = m_scanner.peek();
-      if (token.type == Token::BLOCK_ENTRY ||
-          token.type == Token::BLOCK_SEQ_END) {
-        eventHandler.OnNull(token.mark, NullAnchor);
+      const Token& token_ = m_scanner.peek();
+      if (token_.type == Token::BLOCK_ENTRY ||
+          token_.type == Token::BLOCK_SEQ_END) {
+        eventHandler.OnNull(token_.mark, NullAnchor);
         continue;
       }
     }