Hide irrelevant variables

[Sumukh]

It's easy to get overwhelmed when running this on a project:

We should hide irrelevant variables that haven't changed in a while.

The patch for this in the meantime would be to grow python tutor frame/objects upwards - that way the most recent frame has the attention. That definitely does not solve the issue (changes could be happening in the global frame and you wouldn't notice it)

[Sumukh]

Another approach (purely in JS): Capture the state before execution of the first line - hide all of that - but monitor those refs for changes. If anything changes - render that in the global scope (otherwise ignore)

(could become slightly more complex since there'd be a bit of recursive tracking)