Add callback to respond to errors when a component does not initialise in createAll

[romaricpascal]

What

Add an option to createAll that allows services to pass a callback function to createAll that will be called if a component fails to initialise (or GOV.UK Frontend is not supported).

Why

So services can react to errors happening during component initialisation with createAll, for example sending a report to an error monitoring service

Who needs to work on this

Developers

Who needs to review this

Developers

Done when

• We've decided on the arguments and name of that function
• We've implemented the function
• The feature is documented

[romaricpascal]

As a starter, the callback will be added as third parameter, passed either in place of the scope or in an object that contains both scope and the callback. A future piece of work will look at avoiding to have to provide null when the component does not need a config.

[patrickpatrickpatrick]

Going to close as it's been merged into the WIP branch with documentation written for it.