Add option to skip Batch API UI

Problem/Motivation

By default we retain the traditional Batch API UI and simulate status of the batch by intercepting queue APIs.

We should add an option which redirects the user somewhere, like admin/content, instead of showing the old UI.

This is because the UI is not used to work the batch any longer, and the user might believe they cannot use the site while it is running.

We already provide ways of inspecting the status of the batch, via a Toolbar item and dedicated report page

Steps to reproduce

Proposed resolution

Remaining tasks

User interface changes

API changes

Data model changes