* Include the option to add customized buttons to the toolbar
* Fix all lint problems, export for the export ones.
* Mimic the previous module and namespace declaration.
Somehow this manages to export MediumEditor as a single object,
and define all the relevant types inside the MediumEditor namespace.
* Delete the linter configuration
This module still do not pass the linter tests.
I do not know how to fix the remaining issues, so I disable the linter until a brighter mind can fix these problems.