Merge branch 'mnt/drop_py2734' into 'master'

.gitlab-ci.yml

CHANGELOG.rst

README.rst

doc/fsl.utils.deprecated.rst

doc/fsl.utils.rst

fsl/data/dicom.py

fsl/data/gifti.py

fsl/data/image.py

fsl/data/imagewrapper.py

fsl/data/mesh.py

fsl/utils/async.py

fsl/utils/callfsl.py

fsl/utils/deprecated.py

fsl/utils/platform.py

fsl/utils/run.py

fsl/utils/transform.py

fsl/wrappers/wrapperutils.py

requirements-extra.txt

requirements.txt

setup.py