OpenRTB config.

     | Value | Description                                                                |
     |-------|----------------------------------------------------------------------------|
     | 1     | Audio Ad (Autoplay)                                                        |
     | 2     | Audio Ad (User Initiated)                                                  |
     | 3     | Expandable (Automatic)                                                     |
     | 4     | Expandable (User Initiated - Click)                                        |
     | 5     | Expandable (User Initiated - Rollover)                                     |
     | 6     | In-Banner Video Ad (Autoplay)                                              |
     | 7     | In-Banner Video Ad (User Initiated)                                        |
     | 8     | Pop (e.g., Over, Under, or Upon Exit)                                      |
     | 9     | Provocative or Suggestive Imagery                                          |
     | 10    | Shaky, Flashing, Flickering, Extreme Animation, Smileys                    |
     | 11    | Surveys                                                                    |
     | 12    | Text Only                                                                  |
     | 13    | User Interactive (e.g., Embedded Games)                                    |
     | 14    | Windows Dialog or Alert Style                                              |
     | 15    | Has Audio On/Off Button                                                    |
     | 16    | Ad Provides Skip Button (e.g. VPAID-rendered skip button on pre-roll video)|
     | 17    | Adobe Flash