Cdp-py

* Added DeviceData data item (0x8042)

* Bug Fixes

* Added Image Discovery V2 (0x0171), and Image Notification V2 (0x0172)
* Added POE System Stats V2 data item (0x0173)
* Added Bounding Box Report (0x016A)
* Added Bounding Cylinder Report (0x016B)
* Added boundary status data item (0x0176)
* Added positionless boundary status data item (0x0177)
* Added User Defined V3 data item (0x0179)
* Added Clock Packet (0x80AD) and NTC Command Acknowledge (0x80B0) data items

* Added new Bootload Progress data item (0x0160)
* Added new Topology Info data item (0x0157)
* Added new Ptp Info data item (0x0158)
* Added new NT Real Time Mapping data item (0x015A)
* Added the Set Persistent Property (0x015B)
* Added Get Persistent Property Value (0x015C)
* Added Get Persistent Property List (0x015D)
* Added Get Persistent Property Value Response (0x015E)
* Added Get Persistent Property List Response (0x015F)
* Added new Set Diagnostic LED data item (0x803D)
* Added new linkMD Cable Diagnostic data item (0x0163)
* Added new POE System Stats data item (0x0165)
* Added new Polar Coordinates V1 data item (0x0164)

* Added getters for the flags in the Position V3 data item
* Changed attribute type for final field in QuaternionV2 data item

* Fixed parsing issue with the README.md file