Merged in feature/document (pull request #36)

Document CRUD

* doccreate

* dochashlocandget

* depsandtodo

internal/document/clean/service.go

@@ -0,0 +1,18 @@
+package documentclean
+
+import "errors"
+
+type Service struct {
+}
+
+func New() *Service {
+	return &Service{}
+}
+
+func (s *Service) IsValidVersion(v int32) error {
+	if v <= 0 {
+		return errors.New("document clean code version must be > 0")
+	}
+
+	return nil
+}