Issue #2574789 by MegaChriz: Wrong processor settings set in FeedsUIUserInterfaceTestCase::testImporterImport()

Issue #2542416 by twistor, MegaChriz: Allow sources and targets to be marked as deprecated and hide them from the UI.

Issue #2333029 by twistor, MegaChriz: Extend mapping API to allow for defaults and multiple callbacks

Issue #2218999 by fietserwin: Fixed Warning: Invalid argument supplied for foreach() in element_children() (line 6420 of includes\common.inc).

Issue #2305929 by twistor, MegaChriz: Show message that mapping settings must be saved after changes.

Issue #1561200 by szt, osopolar: Added Use machine names for better identification of similar field names.

Issue #777888 by WorldFallz, liquidcms, firfin, tmsimont | timwood: Followup to importing importers.

Issue #1555974 by twistor | andyg5000: Fixed Save button should also add field mapping; Add button should also save config changes.

Issue #777888 by WorldFallz, liquidcms, firfin | timwood: Added UI to import views-style exportable (a.k.a. How to import importers?).

Issue #1248710: Use the core-provided machine_name FAPI element for the importer machine name field.