Issue #1891516 by sun, Berdir, chx: Remove $install parameter from DrupalUnitTestBase::enableModules(), encourage to create individual schema tables only.

Issue #1331486 by katbailey, chx, sun, beejeebus, amateescu: Move module_invoke_*() and friends to an Extensions class.

Revert "Issue #1331486 by katbailey, chx, sun, beejeebus, amateescu: Move module_invoke_*() and friends to an Extensions class. Broke core tests after commit."

This reverts commit c80c3e18.

Issue #1331486 by katbailey, chx, sun, beejeebus, amateescu: Move module_invoke_*() and friends to an Extensions class.

Issue #1779026 by dagmar, tim.plunkett, sun, heyrocker: Convert Text Formats to Configuration System.