Handle data_path property for instance entity

.../app/admin/components/dataset/dataset-form.component.html

...rc/app/admin/components/dataset/dataset-form.component.ts

client/src/app/admin/components/dataset/index.ts

...pp/admin/components/instance/instance-form.component.html

.../app/admin/components/instance/instance-form.component.ts

...n/components/shared/data-path-form-control.component.html

...min/components/shared/data-path-form-control.component.ts

client/src/app/admin/components/shared/index.ts

.../app/admin/containers/dataset/edit-dataset.component.html

...rc/app/admin/containers/dataset/edit-dataset.component.ts

...c/app/admin/containers/dataset/new-dataset.component.html

...src/app/admin/containers/dataset/new-dataset.component.ts

...pp/admin/containers/instance/edit-instance.component.html

.../app/admin/containers/instance/edit-instance.component.ts

...app/admin/containers/instance/new-instance.component.html

...c/app/admin/containers/instance/new-instance.component.ts

client/src/app/metamodel/models/dataset.model.ts

client/src/app/metamodel/models/instance.model.ts

server/src/Action/DatasetFileExplorerAction.php

server/src/Action/DownloadFileAction.php