Refactoring

Core

• Throw proper errors when thumbnails cannot be generated 
• Removed config/blueprints directory with dead block blueprints and moved default blueprints for site, page and file to in-code arrays in Kirby\Cms\Core::blueprints()
• Removed Kirby\Toolkit\Properties trait from Kirby\Api\Api, Kirby\Cms\Api, Kirby\Email\Email,  Kirby\Email\Body, Kirby\Cms\Auth\Status, Kirby\Cms\App, Kirby\Cms\ContentTranslation, Kirby\Cms\ModelWithContent, Kirby\Toolkit\Pagination , Kirby\Http\Uri , Kirby\Cms\FileVersion, Kirby\Filesystem\Asset, Kirby\Filesystem\File, Kirby\Image\Image classes and Kirby\Filesystem\IsFile trait
• Kirby\Cms\Language, Kirby\Cms\Plugin, Kirby\Cms\Role and Kirby\Cms\StructureObject don't extend Kirby\Cms\Model (and thus also don't use the Kirby\Toolkit\Properties trait) anymore
• Kirby\Cms\Structure extends Kirby\Cms\Items and Kirby\Cms\StructureObject extends Kirby\Cms\Item
• New Content namespace
  • Moved the Content, ContentTranslation and Field classes into the new namespace (compatibility aliases are provided for now)
  • New internal ContentStorage class that currently holds more of the storage related business logic
  • New internal ContentStorageHandler interface and internal PlainTextContentStorageHandler class to bundle all low-level content logic in one place
• Whoops is now generally disabled during PHPUnit test runs to reduce memory usage during tests

Panel

• More frontend unit tests
• Cleaned up k-toolbar component
• New drawer component structure:

  <k-overlay type="drawer">
    <form class="k-drawer" method="dialog">
      <k-drawer-notification />
      <k-drawer-header />
      <k-drawer-body>
        <k-drawer-fields />
      </k-drawer-body>
    </form>
  </k-overlay>

• Portals: Dialogs, Drawers and other Overlays are now separated into different portals. This is done by setting the overlay type:
  • <k-overlay type="dialog">
  • <k-overlay type="drawer">
  • <k-overlay>
    An overlay without a type will use the default overlay portal. Separating them into different portals gives us more control over z-index and layering of elements.
• Removed v-model from k-form and k-fieldset
• Removed $listeners usage from k-draggable, k-button and subcomponents, k-link, k-headline, k-form, k-block, k-block-title, k-box, k-image, k-content-item
• Made k-bubble more flexible
• Use the Vue object syntax for dynamic :style attributes to enhance the robustness and security
• Reduce JS forEach usage