Add API to support "textless" link

[maxime-rainville]

In some context, the link title will not be coming from the Link object itself. The link will be attached to some other element. e.g.: Adding a link to a generic icon on a page.

Developers need to option to hide the "Link text" field.

Story

As a content author, I want clarity when filling in my link data about what where the title will come from.

Acceptance criteria

• An API is provided to developers so they can choose to hide the "Link text" field in specific instances.
• The API is properly documented.
• The responsibility for how to render the link in these instances is left to the developer choosing to implement this approach.

PRs

• NEW Allow developers to exclude LinkText field #215