Refactor how we manage drafts in Formik about opencrvs-core

[jpye-finch]

I would steer towards auto saving ideally. But could we reduce the number of instances. ie on tab out of a form field, on 'Next' to a new form tab. Or in the future when we consider a Gov.uk experience on 'Continue' to the next page and set of questions.

In terms of UX and giving the user peace of mind.
I am considering two options:

1. In the header we have a label 'Saved' that changes to 'Saving...', then 'Saved'. Example is Medium when you start a new story: https://medium.com/p/dff43a182b4f/edit. Presents to the user what the system is doing (autosaving).

2. Have a Save Draft button in the header. With no feedback to what the system is doing (autosaving). User testing will come back saying they want a save button if we don't give any system feedback that the application is auto saving.

[euanmillar]

So this has been resolved by only saving on user interaction on the Continue click or "Save and Exit" click. Plus we now save all the drafts to IndexedDB and retrieve them from there.