Merge pull request #20285 from owncloud/add-integrity-checker

core/ajax/update.php

core/command/integrity/signapp.php

core/command/integrity/signcore.php

core/command/upgrade.php

core/js/integritycheck-failed-notification.js

core/js/setupchecks.js

core/js/tests/specs/setupchecksSpec.js

core/register_command.php

lib/private/integritycheck/checker.php

...e/integritycheck/exceptions/invalidsignatureexception.php

lib/private/integritycheck/helpers/applocator.php

lib/private/integritycheck/helpers/environmenthelper.php

lib/private/integritycheck/helpers/fileaccesshelper.php

...tegritycheck/iterator/excludefilebynamefilteriterator.php

...ritycheck/iterator/excludefoldersbypathfilteriterator.php

lib/private/server.php

lib/private/templatelayout.php

lib/private/updater.php

resources/codesigning/core.crt

resources/codesigning/core.key