Added gridded on RAW

[thomafred]

Changes

• Added odp-utils package.
• Added gridded on RAW implementation to utils.
• Added py.typed files.

Note on Python version

Zarr depends on Python 3.10 or newer, however our SDK needs to support Python 3.9 or newer. As a result, zarr is an optional dependency for the odp-utils-package. If the zarr-package is not installed, gridded functionality will be disabled and the user will get a warning before the import error if they attempt to use it:

>>> from odp.utils.gridded import OdpStoreV3
/home/tom/project/odf/odp-sdk-python/src/utils/odp/utils/gridded/__init__.py:20: UserWarning: Zarr not installed. Gridded support not enabled
  warnings.warn("Zarr not installed. Gridded support not enabled")
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: cannot import name 'OdpStoreV3' from 'odp.utils.gridded' (/home/tom/project/odf/odp-sdk-python/src/utils/odp/utils/gridded/__init__.py)

[thomafred]

Rebased with master