Course CRUD implementation, extensive change of id from String to Long

...java/org/fuseri/model/dto/certificate/CertificateDto.java

...ain/java/org/fuseri/model/dto/common/DomainObjectDto.java

...ain/java/org/fuseri/model/dto/course/CourseCreateDto.java

.../src/main/java/org/fuseri/model/dto/course/CourseDto.java

...rc/main/java/org/fuseri/model/dto/lecture/LectureDto.java

...odel/src/main/java/org/fuseri/model/dto/user/UserDto.java

application/module-language-school/pom.xml

.../org/fuseri/modulelanguageschool/common/DomainObject.java

...org/fuseri/modulelanguageschool/common/DomainService.java

...odulelanguageschool/common/ResourceNotFoundException.java

...n/java/org/fuseri/modulelanguageschool/course/Course.java

.../fuseri/modulelanguageschool/course/CourseController.java

.../org/fuseri/modulelanguageschool/course/CourseFacade.java

.../org/fuseri/modulelanguageschool/course/CourseMapper.java

.../fuseri/modulelanguageschool/course/CourseRepository.java

...org/fuseri/modulelanguageschool/course/CourseService.java

.../org/fuseri/modulelanguageschool/user/UserController.java

.../org/fuseri/modulelanguageschool/user/UserRepository.java

...ava/org/fuseri/modulelanguageschool/user/UserService.java

...language-school/src/main/resources/application.properties