Add an "expand" icon

[tschaka1904]

Refrence: /patterns/icons/

Could we add a expand button? Something like that: https://goo.gl/images/eiyuth

[khawkins98]

Yes, I think this would be a good idea.

There's an open task to review/improve/add icon fonts -- making a cross link to that issue: ebiwd/EBI-Icon-fonts#6