Improved some metrics

...ice/rest-service/src/main/resources/application-local.yml

...vice/rest-service/src/main/resources/application-prod.yml

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

.../services/src/main/java/at/tuwien/config/SparkConfig.java

.../main/java/at/tuwien/service/impl/HibernateConnector.java

...in/java/at/tuwien/api/semantics/TableColumnEntityDto.java

...main/java/at/tuwien/entities/database/DatabaseAccess.java

...c/main/java/at/tuwien/entities/identifier/Identifier.java

.../entities/src/main/java/at/tuwien/entities/user/User.java

...rvice/src/main/java/at/tuwien/endpoints/UserEndpoint.java

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

...ice/rest-service/src/main/resources/application-local.yml

...vice/rest-service/src/main/resources/application-prod.yml

...rvices/src/main/java/at/tuwien/config/DataCiteConfig.java

...a-service/test/src/main/java/at/tuwien/test/BaseTest.java