Issue #2017859 by valdo: Permissions export configuration and import configuration are used in config.routing.yml but not implemented.

Issue #1998576 by beejeebus, alexpott, swentel: Make the config import process use full config trees again.

Issue #1944472 by larowlan, quicksketch, effulgentsia: Add generic content handler for returning dialogs.

Issue #1821548 by heyrocker, swentel, Dean Reilly, dawehner, alexpott, vijaycs85, jhedstrom, adamdicarlo: Add a 'diff' of some kind to the CMI UI.

Issue #1864066 by sun, andypost, tim.plunkett: Simplify hook_menu_local_tasks() and MENU_DEFAULT_LOCAL_TASK usage.

Issue #1697256 by heyrocker, alexpott, sun, xjm, webchick: Create a UI for importing new configuration.

This reverts commit 81666e2b. Sorry, did NOT mean to push that; was testing the CMI UI patch.