0.4.3

Maintenance release.

• Move deepali.utils.storage module to deepali.core.
• Add EulerRotation.matrix_() setter.
• Add LogLevel convenience initialization methods.
• Fix setting default log_level in configure_logging().
• Fix flattening of direction cosines matrix in write_sitk_iamge().
• Remove pyyaml dependency, only use ruamel.yaml instead.
• Install conda-devenv and conda-lock in conda environment.