Add support for Nemo Canary model

[istupakov]

Implement decoding of Nemo models with a transformer decoder:

• https://huggingface.co/nvidia/canary-180m-flash
• https://huggingface.co/nvidia/canary-1b-v2

[DavidAntonin]

https://huggingface.co/nvidia/canary-1b-v2 seems very good with language settings