1.0.0 Release Plan

[martinRenou]

This issue tracks the issues and PRs that should be fixed/included for the major 1.0.0 release.

[martinRenou]

We should remove the classic template support in the 1.0.0 release. Instead there should probably be a Notebook 7 template available, or we can just live with the --show-margins option introduced in #1263.

[jtpio]

Are there any other (potential breaking) major changes to consider?

Or should this 1.0 release be more about promoting the current 0.5.x to 1.0.0?