NF: first draft implementation of itab reader.

[robbisg]

Reference issue (if any)

Draft #12439

What does this implement/fix?

This implementation aims at solving the #12439 enhancement, thus creating a reader for ITAB MEG files.
We added the basic reader class for both raw and mhd data, constants and a draft test function.

In this PR we did not provide a test file, however we can provide it wherever you prefer (mne-testing-data?).

Additional information

[robbisg]

Sorry, we didn't check these style problems, LGTM!

[larsoner]

Most CIs won't run until the style CIs are happy, can you look into the failures here for example?

https://dev.azure.com/mne-tools/mne-python/_build/results?buildId=37794&view=logs&jobId=c1ec3add-0fcd-52ea-530a-328457bbfb2e&j=c1ec3add-0fcd-52ea-530a-328457bbfb2e&t=b97fc2b5-2b32-501d-868f-9d410a8f7a30

For the vulture one for example it's rightfully picking up that _make_itab_name is not used, so you should also comment out that function for now to make it happy (or uncomment the call to it in the test for now)

Let me know if you need help and/or want me to look over the code!

[robbisg]

Hi @larsoner , thanks for the reply. I don't think that at this stage you should look at the PR since it is a super draft and don't want to waste your time. I will check CIs output and fix them.
The only thing you can check is the test function, is it ok to check shape and alignment of data with a reference mat file?

[robbisg]

Still work in progress. I fixed some lint issues and added checks.