[ntuple] Binary format RC3

[jblomer]

Version leading into the 1.0 format. Final cleanups and removal of backward compatibility code for previous experimental anchors.

[github-actions[bot]]

Test Results

    18 files      18 suites   3d 18h 36m 23s ⏱️  2 699 tests  2 697 ✅ 1 💤 1 ❌ 46 129 runs  46 128 ✅ 0 💤 1 ❌

For more details on these failures, see this check.

Results for commit 2a90c5f7.

:recycle: This comment has been updated with latest results.

[jblomer]

Draft for now. We don't want to merge it before CHEP in order to not impact benchmarks done on master.

[jblomer]

Note: clang-format is fine with the changes except that it doesn't understand string literals.