Notebook: Features suggestions

[payne911]

I'd like to propose a few features:

1. A "Cell Execution Queue" indicator and manager (see https://github.com/jupyter/notebook/issues/2340#issuecomment-290101802).
2. A "Variables stored in memory visualizer".
3. A "Threads indicator" to be able to know how many threads are being used by the Kernel.
4. A "Collapse code button" just like it is available for the output of the code itself.
5. A "Copy a cell-along-with-output from one Kernel to another".
6. A "Memory-being-used indicator".
7. Collapsable sections (for big Notebooks with many "sub-chapters".
8. An annotation to get "monospace font" inside Markdowns.

Thank you! :)

Sorry, I'm kind of new around here. Maybe this shouldn't be in "Issues".

[skycreeper2000]

I specifically like Point 2+6 combined, 3, 4+7, 5!!

[Tzeny]

I would very much like to see Point 1 soon <3

[jasonsross]

Point 1 one would be very useful, especially the ability to remove a cell from the execution queue before it runs.

[louis925]

Point 1 and 2 are extremely useful!