Replace basic Images with Media in Core, Caption & Attribution in IU Paragraphs

This initial patch mainly adds new default config useful for installation of the module only.

It does a few backward incompatible things, noted by ⚠️. However these config changes will only affect your site if you re-import with Drupal 8 features or completely uninstall the module, and reinstall it.

Adds support for media in core.
Adds all Content-related image styles based on IU Style guide sizing requirements.
⚠️Replaces iu_image_field with iu_media_field.
Adds fields on iu_image paragraph type for caption description and caption title.
Adds Media support for Images (png, jpg, svg) to image fields.
Exports all media, embed, and entity_browser configs.
Exports the configuration for the entity embed configuration for drupal core ckeditor integration.
Adds dependencies on media, embed, entity_browser, and entity_embed, as well as svg_image_field.

Whoops that was the wrong patch for that comment #3. This is the correct on.

The recent set of comits on the 2.0.x branch have replaced Image fields with Media library fields on several Paragraph types including:

* Callout / Pullquote
* Feature
* Feature Carousel
* Section

Existing Paragraph that contain references to images will NOT be migrated to Media entities and only new paragraph will gain the ability to reference or upload new Media (as opposed to the simple image field).

We also did several naming cleanups for new installs to follow convention on field names not strictly unique to the IU functionality, including field_media_image, field_media_title, field_media_svg, etc.

This work was ultimately released on the 2.1.x branch and released in 2.1.0

Issue queue cleanup.