Optionally hide cell outputs

[okennedy]

What pain point is this feature intended to address? Please describe.

• In some situations, the output of a module is undesirable. For example:

  • Presenting notebooks... some outputs are not relevant to the presentation
  • Virtually identical intermediate steps: e.g., chains of SQL. The intermediate datasets clutter up the workflow and make it harder to view.
  • Spreadsheet mode: If I have a spreadsheet module displaying an editor right after exactly the same dataset, it can be frustrating.

• A more general problem is that we might want to hide module entirely:

  • A 'Focus Artifact' button (c.f. #27)
  • Presentations where you don't want to show everything
  • "hide everything under a particular header level.

Describe the solution you'd like

• [ ] Add a "hide output" toggle on each module
• [ ] Update the CSS/etc... to actually hide the module output
• [ ] Make the "hide output" a property of the module that is preserved
• [ ] Automatically hide output when inserting a spreadsheet cell
• [ ] Add a "hide module" toggle on each module
• [ ] Add the CSS/etc... to actually hide the module (e.g., ~= Vizier 1.x Vizual cells)
• [ ] Add a "hide header" to the ToC to hide all cells under a header
• [ ] Add a "focus artifact" button