Issue #3269222 by gausarts: Move more settings into BlazySettings and classes into folders.

- Moved field base formatters from Dejavu into Drupal\blazy\Field namespace.
- Moved field operations from BlazyEntity into Drupal\blazy\Field\BlazyField.
- Changed DIV to FIGCAPTION specific for BlazyFilter captions.
- Added settings by container attributes for all blazy-related filters.
- Moved internal BlazyGrid into Drupal\blazy\Theme namespace.
- Moved internal BlazyLightbox into Drupal\blazy\Theme namespace.