* Allow for custom regular expression validation of links. (#1048)
* Fix the default RegExp for link validation to support port and match the beginning.
* Moved all embed code to seperate folder
* Consolidated embed builders
* Moved embed toolbar items out
* Moved embed code to separate package
* Updated imports
* Removed I from interface names
* Refactored embed button implementation
* Update readme
* Add Link as source for images and videos
Hosted images and videos are supported, but there's no way to actually insert them.
* Always provide an option to add media from link