feat(pb-facsimile): added option to add download icon to trigger down…

[JoernT]

…load of current viewport. Added a demo for the feature

Example:

<pb-facsimile show-download-control="show-download-control">

will display a download icon in the bottom left of the element. Couldn't figure out how to add an icon to the builtin toolbar which would have been more preferrable but does the job for the project here.

To make it work the crossOriginPolicy property of the Viewer needed to be set. It defaults to 'anonymous' and was tested with Zuericher. An additional cors attribute allows to overwrite the default with 'use-credentials' if necessary.

[github-actions[bot]]

:tada: This PR is included in version 2.23.0 :tada:

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot :package::rocket: