Resurrect from post save error middleware

[porsager]

Do you want to request a feature or report a bug?
Feature

What is the current behavior?
Once post save error middleware is reached it's not possible to return to the success path

What is the expected behavior?
A way to return from post save error middleware to resolve the initial promise

Use case
For instance handle a duplicate error (11000) by creating a new identifier which isn't a duplicate and resave the document returning the new save promise to the initial save call.

Please mention your node.js, mongoose and MongoDB version.
node 8.1.4, mongoose 4.11.1, mongo 3.4.6

[vkarpov15]

Thanks for the suggestion, we'll add this feature in a future release.