Update version number for ZFP compressed files from 3 to 4.

See merge request !46

Allow opening an existing ZGY file for writing.

See merge request !45

When passing create arguments from the Python wrapper to OpenZGY/C++, only pass those explicitly specified. Needed for update, and also to make sure the defaults are hard coded just one place.

Allow updating files also in the Python wrapper for OpenZGY/C++. Currently with more restrictions than in native C++. Work in progress.

Miscellaneous unrelated tweaks

See merge request !44

Change the default chunk size when copying from 128x128x0 to 64x256x0 which can be very slightly faster in the cloud case.

Parallel upload to cloud is now on by default. Also change the meaning of segsize to be the actual blob size in seismic store. Not the buffer size which may now be larger.

Updates to build environment

See merge request !43

Handling of empty files

See merge request !41

Update the copyright notice in all files that have been modified this year.

See merge request !42

Test creating and reading back an empty file in the wrapper, i.e. exercising the C++ version of OpenZGY.

In the C++/Python wrapper test, enable the code that allows comparison with the old ZGY-Public accessor where available. (Typically for manual builds only).

Update tests after change in seismic store behavior.

See merge request !40

Separate docker files for testing

See merge request !39

Separate docker files for testing. These files both document and verify the minimal dependencies needed at runtime. The built images may also be useful for end users.

OpenZGY parallel upload to cloud

See merge request !38