Fixing file structure

...org/fuseri/modulecertificate/certificate/Certificate.java

.../modulecertificate/certificate/CertificateController.java

...seri/modulecertificate/certificate/CertificateFacade.java

...seri/modulecertificate/certificate/CertificateMapper.java

.../modulecertificate/certificate/CertificateRepository.java

...eri/modulecertificate/certificate/CertificateService.java

...ava/org/fuseri/modulecertificate/exceptions/ApiError.java

...ificate/exceptions/CustomRestGlobalExceptionHandling.java

.../fuseri/modulecertificate/CertificateControllerTests.java

.../org/fuseri/modulecertificate/CertificateFacadeTests.java

.../org/fuseri/modulecertificate/CertificateMapperTests.java

.../fuseri/modulecertificate/CertificateRepositoryTests.java

...org/fuseri/modulecertificate/CertificateServiceTests.java