lib: download: manager: refactoring: group progress commands to new supercommand 'forward-to-progress'
lib: download: progress: new methods 'markAsOptional' and 'isOptional'
lib: download: progresses: console: honor 'Progress::isOptional()'
lib: download: manager: DownloadEntity: new member 'optional'
lib: internal: worker: metadata: refactoring: new function 'combineDownloadPostActions'
lib: config: removed the option 'cupt::update::keep-bad-signatures'
lib: internal: worker: metadata: __update_release: refactoring: use emplace_back for filling extendedUris
lib: internal: worker: metadata: __update_release: refactoring: compact downloadManager.download() calls
lib: worker: metadata: __update_release: refactoring: checks simulating were useless
lib: worker: metadata: __update_release: refactoring: new functions 'getReleaseCheckPostAction' and 'getReleaseSignatureCheckPostAction'
lib: worker: metadata: __update_release: refactoring: new function '__downloadReleaseLikeFile'
lib: worker: metadata: __update_release: refactoring: new function 'fillHashSumsIfPresent'
lib: worker: metadata: __update_release: refactoring: __downloadReleaseLikeFile: determine 'runChecks' itself
lib: internal: worker: metadata: __update_release_and_index_data: download InRelease if present
lib: internal: cachefiles: verifySignature: refactoring: new function 'openingForReadingSucceeds'
lib: internal: cachefiles: verifySignature: support for self-signed files
lib: internal: cacheimpl: getReleaseInfo: support InRelease files
lib: internal: cachefiles: getReleaseInfo: support skipping PGP headers
lib: internal: worker: metadata: __update_release_and_index_data: display a warning if no type of release file succeeded to download
lib: internal: cachefiles: getDownloadInfoFromRelease: use new 'getPathOfMasterReleaseLikeList'