Add WYSIWYG editor to `content` field

[loevgaard]

Add a WYSIWYG editor to the content field to allow users to easily add/edit terms with HTML

[igormukhingmailcom]

Related article: https://github.com/FriendsOfSylius/SyliusGoose/blob/master/StepByStep/WYSIWYG_EDITOR_IN_ANY_FORM.md

[gabiudrescu]

how about this? https://github.com/monsieurbiz/SyliusRichEditorPlugin

[loevgaard]

As of now I am leaning more and more towards markdown. What do you think?