text: Title: POST adding extra header
  Body: The issue still exists in version 0.10.1 (Flask 0.12.2)
  https://github.com/noirbizarre/flask-restplus/issues/84
  
  curl -X POST **--header 'Content-Type: application/json'** --header 'Accept: application/json' 'http://localhost:5000/api/v1.0/user/peter?password=12345678&email=peter%40abcdef.com'
  
  Response Body:
  {
    "message": "Failed to decode JSON object: Expecting value: line 1 column 1 (char 0)"
  }
  
  `    
      
      @api.expect(parser)
      @api.response(200, 'Success, not created')
      @api.response(201, 'Created')
      @api.response(400, 'Bad request, validation error')
      def post(self,
               username,
               ):
          '''Create a user'''
  
          args = parser.parse_args(strict=True)
          password = args['password']
          email = args['email']
  
          user = User(username, password, email)
  
          if user.create():
              return True, 201
              # TODO add location header
          else:
              return False, 200
  `
  
  ![user api](https://user-images.githubusercontent.com/2574849/32971881-a7e7df96-cbef-11e7-9285-341d75f92598.png)
  