Revert "Issue #2403307 by dawehner, marthinal, clemens.tolboom, tedbow, Wim Leers, neclimdul, Crell, klausi, andypost, e0ipso: RPC endpoints for user authenication: log in, check login status, log out"

This reverts commit da16ae56.

Issue #2403307 by dawehner, marthinal, clemens.tolboom, tedbow, Wim Leers, neclimdul, Crell, klausi, andypost, e0ipso: RPC endpoints for user authenication: log in, check login status, log out

Issue #2226317 by GemVinny, Manuel Garcia, joginderpc, Oostie, LewisNyman, juho.lehmonen, amanire, ibbwebguy, aczietlow, studiozut, alexpott, emma.maria, rteijeiro: Divs in the container-inline wrapper should be inline-block instead of inline

Issue #2506449 by dagmar, willzyx, mikeohara, yoroy, catch: Transform "Clear log messages" submit button into a link in admin/reports/dblog

Issue #2491253 by Chernous_dn, rudraram, mortendk, pjbaert, LewisNyman, mayurjadhav, aadrian, joginderpc: Remove file.admin.css from file module

Issue #2573635 by Wim Leers, Mac_Weber, lluvigne, dawehner, dimaro, ConfuciusDa1st, rootwork, BR0kEN, unstatu: Url::fromUri() should accept protocol-relative URLs

Issue #2598038 by alexpott, sethcardoza, quietone, Jaesin: Invalid passwords after D7 to D8 migration

Issue #2722621 by anoopjohn: Fix Drupal.Commenting.FunctionComment.InvalidReturn and Drupal.Commenting.FunctionComment.VoidReturn

Issue #2705921 by jmk61, Vinay15, chgasparoto, jhodgdon, vegantriathlete, kjl16, joachim: docs for postCreate() should clarify create does not mean save

Issue #2740499 by nesta_, lluvigne, rajeshwari10, jhodgdon, er.pushpinderrana, joachim: parameter to DiscoveryTrait::doGetDefinition() is incorrectly documented as optional

Issue #2731309 by Vinay15, Ashish.Dalvi, joachim, jhodgdon: docs for deprecated functions in core/includes/entity.inc refer to deprecated entityManager()

Issue #2737607 by generalredneck: Migration Source Plugins are not extendable because of ambiguous database field names

Issue #576296 by no_angel, joachim, dagmar, jhodgdon, coderintherye, yoroy, xjm: Remove redundant description for some permissions

Issue #2533220 by snehi, pjonckiere, mirom, chx, jhodgdon, dawehner: RouteBuilderInterface has no docblock

This reverts commit 74ccd070.

Issue #2682585 by heddn, dscl, hanoii, willwh, hussainweb: Rename MigrationCreationTrait as it no longer creates migrations - it configures them

Issue #2735045 by klausi, dawehner, jibran: Convert StandardTest to BrowserTestBase by introducing a AssertLegacyTrait and new assertions on the WebAssert

Issue #2466197 by alexpott, heddn, dawehner, pjcdawkins: Staging directory should not have to be writeable

Issue #2712637 by klausi, jibran, dawehner, simensen, JeroenT: Update stack/builder for Symfony 3 compatibility

Issue #2726645 by klausi: Do not @deprecate EntityManager until all usages are removed (helps the Symfony 3 update)

Issue #2477899 by dawehner, kevin.dutra, borisson_, bojanz, catch, amateescu: Multiple valued Base fields won't work in Views

Issue #2718717 by damiankloip: Assertion error when paging a view using an entity autocomplete exposed filter

Issue #2717483 by pguillard, mikeryan: Empty migration_dependencies gives "Unsupported operand types"

Issue #2723611 by Ashish.Dalvi, Sagar Ramgade, gaurav.pahuja, Sonal.Sangale, marvin_B8, valthebald, Mile23, xjm: Remove entity_load* usage for node entity type

Issue #2561993 by jhedstrom, jonathanjfshaw, yoroy, emma.maria, mpdonadio: Better labelling for Date time form select elements