Add support for C++11 range-based for-loop

for(auto &o : my_json_value->u.object)
{
std::cout << o.name << std::endl;
}
And similar for arrays. No type checking, unfortunately - I couldn't
manage that.

Fix indentation

json.h

@@ -107,13 +107,31 @@ typedef struct _json_value
 
          } * values;
 
+         #if defined(__cplusplus) && __cplusplus >= 201103L
+         decltype(values) begin () const
+         {  return values;
+         }
+         decltype(values) end () const
+         {  return values + length;
+         }
+         #endif
+
       } object;
 
       struct
       {
          unsigned int length;
          struct _json_value ** values;
 
+         #if defined(__cplusplus) && __cplusplus >= 201103L
+         decltype(values) begin () const
+         {  return values;
+         }
+         decltype(values) end () const
+         {  return values + length;
+         }
+         #endif
+
       } array;
 
    } u;