new: TrainingConfig class; added training configs for each model. #32
  Add this suggestion to a batch that can be applied as a single commit.
  This suggestion is invalid because no changes were made to the code.
  Suggestions cannot be applied while the pull request is closed.
  Suggestions cannot be applied while viewing a subset of changes.
  Only one suggestion per line can be applied in a batch.
  Add this suggestion to a batch that can be applied as a single commit.
  Applying suggestions on deleted lines is not supported.
  You must change the existing code in this line in order to create a valid suggestion.
  Outdated suggestions cannot be applied.
  This suggestion has been applied or marked resolved.
  Suggestions cannot be applied from pending reviews.
  Suggestions cannot be applied on multi-line comments.
  Suggestions cannot be applied while the pull request is queued to merge.
  Suggestion cannot be applied right now. Please check back later.
  
    
  
    
Instead of using HF's PretrainedConfig and dumping all model parameters and hyperparameters into one place, TrainingConfig clearly separates the model's PretrainedConfig from training parameters like batch size, learning rate, etc.
In addition, this PR adds extensions of PretrainedConfig for each baseline (LTSMConfig, DLinearConfig, PatchTSTConfig, and InformerConfig). This exposes the expected model parameters to users and it provides reasonable defaults as backup.