Add NGSI-LD support

[WillFreitag]

Beside V2, LD protocol has to be supported

• Change existing protocol NGSI to NGSI-V2
• Add protocol NGSI-LD
• Implement support
• Change Readme.md

[WillFreitag]

In Release 1.1.0, experimental support is implemented.
As soon as a stable version of Orion LD is available, this work will be continued.