Neural-admixture

- Update dependencies to avoid breaking changes and speedup data reading.
- Drop columns containing only NaNs from the input matrix.

- Added mean imputation for missing data
- Mean imputation is now the default option for imputing

**Full Changelog**: https://github.com/AI-sandbox/neural-admixture/compare/v1.3.1...v1.4.0

- Fixes 22 (warmup training breaking for different initializations).
- Removed unnecessary print in training loop.

- Added warmup training for initialization of Q to improve training stability.
- Changed default P initialization to 'pckmeans'.
- Changed convergence check so it is performed after 15 epochs.
- Changed default learning rate to 1e-5 instead of 1e-4.
- Added acceleration for Apple Metal in compatible devices (M1 and M2 family).

- Update docs

- Automatic version bump
- Changed version log in entrypoint