* Respect sequence_len in config for `type: llama2_chat`
It was hardcoded to `4096` I am not sure why? This updates it to pull from the config.
cc: @winglian
* Update llama2_chat.py
* apply black formatting
* fix tokenizer
* update test data
* lint fixtures
* support for sharegpt with assistant talking first, better masking of assistant token, allow remap of roles from dataset
* invalid role is actually not possible
* update tokenized fixture for corrected labels
* use fastchat conversations template
* require fastchat (fschat) pip install
* handle roles dynamically from conversation
* tweak fastchat conversation with a monkeypatch to get individual turns
* fix up so it works with multiple conversation styles, and don't strip the turns
* fix sharegpt fixture now that we're using a more correct tokenization
* use a new prompter and support fastchat conversation type
* use sharegpt from prompt strategies now
* update docs, add chatml template
* add a newline after im_end token
* ensure we correctly set system message
* update per PR feedback to handle deprecated sharegpt types
* don't add duplicate wandb req
* make sharegpt fields configurable from yml
* llama2 fixes
* don't fail fatally when turns are improper
* experimental llama 2 chat support
* few small fixes
* llama2_chat
* small fix to follow original implementation
* small fixes and added fixtures/tests
* fix -mixed up inference and finetuning conversations
* args - small fix
* small fix
* small adjustment and warning
* fix with pre-commit
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Co-authored-by: Jan Philipp Harries <jpdus@users.noreply.github.com>
