Init autoreload feature

[Splines]

3b1b and me added a new --autoreload CLI flag to Manim in 3b1b/manim#2268. See 3b1b/manim#2252 for a detailed description of what it is about and also some test code to experiment with.

In this PR, we bring this new flag to Manim Notebook and activate it by default since its performance penalty is really negligible.

[Splines]

Yeah, --autoreload is getting even more powerful with this PR by 3b1b. In the long run we may not even need the reload() command anymore 😅 But let's keep both in for now since there might be circumstances when the autoreload does not work.

[bhoov]

Since this is a new feature, it breaks on my existing environment of manimgl

manimgl: error: unrecognized arguments: --autoreload

I have always felt that it is important for this exxtension to support existing manim projects. If we do not support the existing projects, I feel we will have a more difficult time with adoption.

In general, manimgl is a difficult package to base an extension on because it has no commitment to backwards compatibility, and if I am developing a scene in manimgl I have to "pin" the manimgl version in my working env to prevent new changes from breaking my code.

Is it possible that we can prevent automatically passing the --autoreload flag for manimgl versions that are too old?

[Splines]

Is it possible that we can prevent automatically passing the --autoreload flag for manimgl versions that are too old?

Yes, for sure, that's what #97 will be addressing.

If we do not support the existing projects, I feel we will have a more difficult time with adoption.

And yes, I definitely see the point and many users won't have the most recent version. So detecting the Manim version is essential. Let's do that in another PR that addresses #97. We could then also show an update notification, see my comment here.

[bhoov]

Perfect, then let's address my concern in a followup. Thanks!