Merge branch '507-improve-doi-resolving' into 'dev'

dbrepo-metadata-db/migration/16/update_id.sql

...e/api/src/main/java/at/tuwien/api/doi/AffiliationDto.java

...ervice/api/src/main/java/at/tuwien/api/doi/AuthorDto.java

...a-service/api/src/main/java/at/tuwien/api/doi/DoiDto.java

...rvice/api/src/main/java/at/tuwien/api/doi/LicenseDto.java

...-service/api/src/main/java/at/tuwien/api/doi/LinkDto.java

...ice/api/src/main/java/at/tuwien/api/doi/ReferenceDto.java

...vice/api/src/main/java/at/tuwien/api/doi/ResourceDto.java

...ain/java/at/tuwien/api/doi/ResourceRepresentationDto.java

...rc/main/java/at/tuwien/api/doi/TimeRepresentationDto.java

...a-service/rest-service/src/main/resources/application.yml

...ac/tuwien/ifs/dbrepo/gateway/CrossRefGatewayUnitTest.java

...ac/tuwien/ifs/dbrepo/service/MetadataServiceUnitTest.java

...service/rest-service/src/test/resources/doi/database.json

...-service/rest-service/src/test/resources/doi/dataset.json

.../rest-service/src/test/resources/doi/journal-article.json

...t-service/src/test/resources/doi/proceedings-article.json

...in/java/at/ac/tuwien/ifs/dbrepo/config/GatewayConfig.java

...java/at/ac/tuwien/ifs/dbrepo/gateway/CrossRefGateway.java

...c/tuwien/ifs/dbrepo/gateway/impl/CrossRefGatewayImpl.java