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.

Expose both the coding range stored in the file and the sanitized version, to allow applications to handle inconsistent files better. Supported both in C++, Python, C++ Wrapper, and the ZgyPublic compatibility wrapper.

Add ZgyUtils.alturl() for wrapping SDAPI.getSerializedContext(), as was done in the old ZGY. Implemented for C++, the Python Wrapper, and SdGlue.