Issue #3072702 by alexpott, Wim Leers, mikelutz, xjm, catch, Berdir, tedbow, shaal, webchick, Mixologic, heddn: Core extensions should not need to specify the new core_version_requirement in *.info.yml files so that 9.0.x can be installed

(cherry picked from commit 3834d60f)

Issue #3085608 by Wim Leers, mikelutz, voleger, larowlan: [Symfony 4] Symfony console command ::execute() methods should return 0 on success

Issue #2902412 by Jo Fitzgerald, andypost, mfernea, andriyun: Fix 'Drupal.Strings.UnnecessaryStringConcat' coding standard

Issue #2937853 by idebr, mfernea, SherFengChong, alexpott, borisson_: Fix 'Drupal.Formatting.MultipleStatementAlignment' coding standard

Issue #2966523 by alexpott, blakemorgan, almaudoh, gapple, Mixologic, amateescu, bojanz: MySQL 8 Support

Issue #2969718 by runeasgar, alexpott: The quick-start script could make it clearer than Ctrl+C is used to kill the server

Issue #2911319 by alexpott, dawehner, mglaman, mradcliffe, heddn, pbirk, danquah, maxstarkenburg, geerlingguy, vaplas, Chelsee, ressa, Chi, jonathanshaw, Mile23, andypost, larowlan, phenaproxima, droffats, kim.pepper, scotty, dsnopek, cashwilliams, borisson_, Mixologic, gerzenstl, David Radcliffe: Provide a single command to install & run Drupal

Issue #2803891 by Jo Fitzgerald, pfrenssen, mfernea, gaurav.kapoor: Fix 'Drupal.Commenting.FunctionComment.ReturnTypeSpaces' coding standard

Issue #2665992 by alexpott, klausi, heykarthikwithu, xjm, tstoeckler: @file is not required for classes, interfaces and traits

Issue #2676346 by alexpott, dawehner: Coding standards check on DB dump fixtures causes PHPCS to out of memory on PHP5.5 and is slow cause of huge files

Issue #2600538 by rakesh.gectcr, anil280988, justAChris, jhodgdon: Incorrect @file description in core/ classes - wrong namespace or class name

Issue #2565259 by plach, Antti J. Salminen, stefan.r, dawehner: Some route serializations in update test database dumps are broken

Issue #1713332 by amateescu, Xen, droplet, bzrudi71, znerol, czigor, pp, wulff, Damien Tournoud: The SQLite database driver fails to drop simpletest tables

Issue #2536644 by tim.plunkett: generate-proxy-class.php should generate the same file regardless of a missing leading slash

Issue #2408371 by dawehner, Fabianx, alexpott, bforchhammer: Proxies of module interfaces don't work

Issue #2497323 by jhedstrom, dawehner, alexpott, larowlan: Create a php script that can dump a database for testing update hooks