Merge branch '290-use-dois-as-pids' into 'dev'

.env.unix.example

.env.win.example

.gitignore

...ce/api/src/main/java/at/tuwien/datacite/DataCiteBody.java

...ce/api/src/main/java/at/tuwien/datacite/DataCiteData.java

...c/main/java/at/tuwien/datacite/doi/DataCiteCreateDoi.java

...api/src/main/java/at/tuwien/datacite/doi/DataCiteDoi.java

.../main/java/at/tuwien/datacite/doi/DataCiteDoiCreator.java

...at/tuwien/datacite/doi/DataCiteDoiCreatorAffiliation.java

...tuwien/datacite/doi/DataCiteDoiCreatorNameIdentifier.java

...rc/main/java/at/tuwien/datacite/doi/DataCiteDoiEvent.java

.../at/tuwien/datacite/doi/DataCiteDoiRelatedIdentifier.java

...c/main/java/at/tuwien/datacite/doi/DataCiteDoiRights.java

...rc/main/java/at/tuwien/datacite/doi/DataCiteDoiTitle.java

...rc/main/java/at/tuwien/datacite/doi/DataCiteDoiTypes.java

...src/main/java/at/tuwien/endpoints/IdentifierEndpoint.java

...rvice/rest-service/src/main/resources/application-doi.yml

...ce/rest-service/src/main/resources/templates/cite_apa.txt

...rest-service/src/main/resources/templates/cite_bibtex.txt

...e/rest-service/src/main/resources/templates/cite_ieee.txt