Add CodeLlama-70b-Instruct-hf (#752)
* Add CodeLlama-70b-Instruct-hf
* add comment to reduce
* Added missing newlines to prompt format for codellama 70b
* remove extra space
* stop tokens
* Remove source newline
* fix preprompt
* fix prompt one last time
* add news
* shorter text
* fix link & remove old tokens
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Co-authored-by: Mishig Davaadorj <dmishig@gmail.com>
