Merge pull request contentful#254 from contentful/prepare-4.2.4

Bump version number and update changelog

Merge pull request contentful#252 from contentful/hotfix/protocol-check

Debug protocol conformance check in fetch by id method

Merge pull request contentful#250 from contentful/hotfix/discardable-…

…result

Add @discardableResult where it was missing

Add new linter rules and format code & comments (contentful#246)

* Improve inline documentation and make doc formatting consistent

* Add more opt-in rules to swiftlint and enforce them

* Bump version number and update changelog

* fixup! Improve inline documentation and make doc formatting consistent

Merge pull request contentful#244 from contentful/feature/logging

Implement configurable logging

Merge pull request contentful#242 from contentful/config/prune-nimble

Prune Nimble; fix deployment version on macOS module header

Merge pull request contentful#240 from contentful/bugfix/tvOS-corrupt…

…ed-target

Bugfix/tv os corrupted target

Merge pull request contentful#239 from contentful/prepare-4.1.1

Bump version to 4.1.1