rename ids; implement file download

api-lib-core/pom.xml

...e/src/main/java/de/ozgcloud/apilib/file/OzgCloudFile.java

...src/main/java/de/ozgcloud/apilib/file/OzgCloudFileId.java

...ain/java/de/ozgcloud/apilib/file/OzgCloudFileService.java

...de/ozgcloud/apilib/file/grpc/GrpcOzgCloudFileService.java

.../apilib/file/grpc/OzgCloudFileDownloadStreamObserver.java

...java/de/ozgcloud/apilib/file/grpc/OzgCloudFileMapper.java

...src/main/java/de/ozgcloud/apilib/user/OzgCloudUserId.java

...ava/de/ozgcloud/apilib/vorgang/OzgCloudVorgangHeader.java

...ava/de/ozgcloud/apilib/vorgang/OzgCloudVorgangStatus.java

...de/ozgcloud/apilib/vorgang/dummy/DummyVorgangService.java

...e/ozgcloud/apilib/vorgang/grpc/OzgCloudVorgangMapper.java

...java/de/ozgcloud/apilib/file/OzgCloudFileTestFactory.java

...ud/apilib/file/grpc/GrpcFindFilesResponseTestFactory.java

...zgcloud/apilib/file/grpc/GrpcOzgCloudFileServiceTest.java

.../de/ozgcloud/apilib/file/grpc/GrpcOzgFileTestFactory.java

...loud/apilib/vorgang/OzgCloudVorgangHeaderTestFactory.java

api-lib-demo/pom.xml

ozg-cloud-spring-boot-starter/pom.xml

pom.xml