## Enter key
Test the Enter key support.
### Notes:
* Expected behavior:
* At the end of a heading should create a new paragraph.
* In the middle of a heading should split it.
* Shift+Enter should move the text to new line.
* The selection should always be moved to the newly created block.
* Select all + Enter should leave an empty paragraph.
* Check:
* Non-collapsed selections.
* Integration with undo.
* ~~Integration with basic styles~~ ([bug](https://github.com/ckeditor/ckeditor5-enter/issues/4)).