refactor: #795 DataView to MessageAlertView and loading way.

lib/core/widgets/http_fail_view.dart

lib/core/widgets/loading_view.dart

lib/core/widgets/message_alert_view.dart

lib/core/widgets/permission_low_view.dart

lib/core/widgets/search_no_result_view.dart

lib/modules/community/faq_list_view.dart

lib/modules/issues/list/issues_view.dart

.../issues/manage/widgets/description_template_selector.dart

lib/modules/issues/manage/widgets/label_selector.dart

lib/modules/mr/commits/commits_view.dart

...ts/group_details/iterations/subgroup_iterations_page.dart

...rojects/group_details/mrs/project_merge_request_page.dart

.../projects/group_details/subgroups/subgroup_list_page.dart

lib/modules/projects/groups/projects_groups_page.dart

lib/modules/projects/starred/projects_starred_page.dart

lib/modules/to_dos/to_dos_view.dart

test/core/widgets/no_data_view_test.dart

...ration_tests/modules/issues/project_issues_page_test.dart

...gration_tests/modules/issues/test_issue_details_page.dart

...ntegration_tests/modules/projects/projects_page_test.dart