update changelog for init checkpoint
#### Februar 2021
+- PR [#154](https://github.com/uma-pi1/kge/pull/154): store checkpoint containing the initialized model for reproducibility
- [9e88117](https://github.com/uma-pi1/kge/commit/9e88117b3bf3f91b1c22f17d88eae2f77b5e3d3e): Add Transformer model and learning rate warmup (thanks nluedema)
- PR [#176](https://github.com/uma-pi1/kge/pull/176): Add TransH model (thanks Mayo42)
