no issue
- `payload.metadata` may not exist in a bookmark card because it's possible to save a mobiledoc document when the card is in it's "unable to parse url" state in the editor
- check for `payload.metadata` object before performing any url transformations to avoid invalid property access
no issue
- adds abolsute->relative and relative->absolute transformer methods to card definitions
- allows for each card to tailor it's transformation to the specific needs of it's payload so that the `mobiledoc` field can be transformed successfully during API serialization/deserialization
requires https://github.com/TryGhost/Ghost-Admin/pull/1293
- updates `oembed` endpoint behaviour
- if an oembed provider is not found then we use `metascraper` to populate a metadata object
- when metadata is returned rather than an oembed response the payload will look like this:
```json
{
"url": "...",
"type": "bookmark",
"metadata": {
"url": "...",
"title": "...",
"description": "...",
"author": "...",
"publisher": "...",
"thumbnail": "...",
"icon": "..."
}
}
```
- adds a `bookmark` card which generates output for the bookmark card:
```html
<figure class="kg-card kg-bookmark-card">
<a href="[URL]" class="kg-bookmark-container">
<div class="kg-bookmark-content">
<div class="kg-bookmark-title">[TITLE]</div>
<div class="kg-bookmark-description">[DESCRIPTION]</div>
<div class="kg-bookmark-metadata">
<img src="[ICON]" class="kg-bookmark-icon">
<span class="kg-bookmark-author">[AUTHOR]</span>
<span class="kg-bookmark-publisher">[PUBLISHER]</span>
</div>
</div>
<div class="kg-bookmark-thumbnail">
<img src="[THUMBNAIL]">
</div>
</a>
</figure>
```
- if a particular bit of data does not exist then the associated html element will not be present
