add blurhash to Picture component

[tttp]

the image uploaded by the camera might be big, and take a while to load when displayed as part of a wall

there is a nice option to generate a super simple placeholder https://github.com/woltapp/blurhash/tree/master/TypeScript that can be saved as a string on SB

changes:

• on field/Camera, generate and upload the blurHash
• on PictureWall, read the blurHash and display it until the image is loaded
  example of a hook to generate a placeholder image based on the blurHash:

https://gist.github.com/ngbrown/d62eb518753378eb0a9bf02bb4723235

[tttp]

Could be used as well for the twitter field (logo)