Simplify Image url handling

[StaehliJ]

Use case description

After an update, it seem that IlImage does nothing special anymore like ImageUrl that only generate an IlImage.

Acceptance criteria

ImageProvider is still easily usable

Proposed solution

Remove both classes and replace with a string each ImageUrl.

Alternatives considered

Do nothing

Is there an existing similar feature request?

• I have searched existing features and found no similar request.

• I have browsed the available API and found no way to achieve the use case I described.

[StaehliJ]

Proposition:

val media: Media
media.imageUrl.url(ImageWidth.W1920)
media.imageUrl.url(ImageWidth.W1920, IlHost.TEST)

val chapter: Chapter
chapter.imageUrl.url(ImageSize.MEDIUM)
  
val defaultDecorator = DefaultImageUrlDecorator(IlHost.PROD) // or custom decorator
media.imageUrl.url(defaultDecorator, ImageSize.MEDIUM)