ListUserPage, CreateUserPage and EditUserPage work, I18N

ListUserPage, CreateUserPage and EditUserPage work, I18N

* I18N: new: trDyn()
* new global_widget.dart: fetching data from the backend, building combobox items
* new: base/validators.dart
* create_user_custom: modified to work
* global_data.dart:
** new loginUserName, loginUserId, loginUserRole
** new: GlobalTranslations, GlobalThemeData
* new widget/message_line.dart
* WidgetForm: refactored: switched from widget list to FormItem list.
* sql_generator:
** byId, delete: fix: missing ':' in ':id'
** INSERT: fix: ignoring primary key
** UPDATE: fix: ignoring hidden fields, errors respecting the primary key
* sql_storage: fix: parameters has strings not dynamics.
* AttendePage: new getRecord(), loadRecord(), hasRecordResponse(),
  hasResponse(), listResponse(), recordResponse()
* new: global.sql.yaml, local.sql.yaml