Update All Python Scripts to nbs similar to `nbdev_update_lib` in v1

[BirkhoffG]

I am wondering why nbdev_update in v2 works differently in v1. In v1, nbdev_update_lib will update all modified python scripts, which is very handy.

However, in v2, to update changes made in the python module, we need to

1. cd python_module
2. nbdev_update python_file.py

This is a cumbersome process. Why not just keep the v1 design by just typing the nbdev_update in the parent directory?

[BirkhoffG]

Also, the document is not very clear in v2.

If you are in the parent directory, then nbdev_update python_module/file.py will not work if your notebooks are in the directory (e.g., in nbs directory). You need to move to the python module first, and update the module.

I don't know if this is intended or just a bug. Anyway, I cannot find clear documentation on nbdev_update, so it would be great if you could document this.

[jph00]

I don't know if this is intended or just a bug.

It's a bug!