Disallow moving for the Parser.

It wouldn't have compiled anyways, since the Scanner and Directive objects inside it are incomplete types at the time of the move definitions.

include/yaml-cpp/parser.h

@@ -28,11 +28,10 @@ class YAML_CPP_API Parser {
   /** Constructs an empty parser (with no input. */
   Parser();
 
-  /** non copyable but movable */
   Parser(const Parser&) = delete;
-  Parser(Parser&&) = default;
+  Parser(Parser&&) = delete;
   Parser& operator=(const Parser&) = delete;
-  Parser& operator=(Parser&&) = default;
+  Parser& operator=(Parser&&) = delete;
 
   /**
    * Constructs a parser from the given input stream. The input stream must