Proposal: Outsource installation of packages (models, data plugins) - WARNING - breaking API change

[edwardchalstrey1]

Closes #253 (see discussion on this issue)

Idea here is to circumvent a lot of the problems we have around package installation for models in the catalog (and more recently data plugins) by completely removing this as a feature of scivision. This branch does that, and I've created a branch on the scivision_examples repo with the same name that updates the intro (Koala) notebook (see here) - take a look under the "Loading the model" header.

Essentially we raise a warning if the package is not installed that explains how to install it (we already had this warning in place in fact!).

I want to spark some discussion here, so feel free to voice your disagreements in the comments below!

TODO:

• Update docs with this change
• Update all gallery notebooks

Further idea

Perhaps there should be a function like:

get_install_code('scivision_classifier')

which simply prints out:

Copy the following line of code into a new notebook cell (or remove the "!" and run in a terminal window):
!pip install -e git+https://github.com/alan-turing-institute/scivision_classifier@main#egg=scivision_classifier

... or alternatively links to the package repo README for packages that are more complex to install

[quantumjot]

I think I'd be sad if this feature went away, esp. if we're targetting less experienced users. I'd rather have the info message (i.e. this PR) as a fallback if the package can't be installed automatically.

[edwardchalstrey1]

I think I'd be sad if this feature went away, esp. if we're targetting less experienced users. I'd rather have the info message (i.e. this PR) as a fallback if the package can't be installed automatically.

@quantumjot that's understandable and it's the reason you added this feature to begin with - I think this somewhat comes at the expense of things being more likely to go wrong with installation where we try to automate it (due to dependencies etc) - my alternative idea for less experienced users which makes use of @ots22 UI feature: #325

[edwardchalstrey1]

If we did merge this, we could also acknowledge the breaking change via switching to version 1.0.0. https://semver.org/