Add some metadata to the readme

Just adding some basic metadata, to make it easier to find this model. Added the same license, languages and gated prompt as [v1](https://huggingface.co/NbAiLab/nb-gpt-j-6B) - please correct me if it should be different for this one :)

README.md

@@ -0,0 +1,16 @@
+---
+license: apache-2.0
+language:
+- 'no'
+- nb
+- nn
+pipeline_tag: text-generation
+extra_gated_prompt: >-
+  You agree to not use the model to conduct experiments that cause harm to human
+  subjects.
+extra_gated_fields:
+  Company: text
+  Country: text
+  Intended Use: text
+library_name: pytorch
+---