Update run_pretraining.py and configuration_aragpt2.py

Update README.md and config.json, and add aragpt2-large model to ARAGPT2_PRETRAINED_MODEL_ARCHIVE_LIST

Update model configuration and mappings

Update config.json with AraGPT2 model and auto mapping

Update README.md

Create LICENSE

Update README.md

added tensorboard logs

Update README.md

allow flax

added citation

Update README.md

Added model files

initial commit