Update buttons

[jasperjansz]

I'm seeing a lot of different button styles in our product, especially the secondary type (admittedly my fault). I'd like to redesign it in a way we can all get behind and push it to our products using the UI library.

There's also the issue of the disabled state of the primary button looking similar to the secondary button.

[andresgalante]

Design consistency across our products is a thing that keeps popping up.

@aulneau @jasperjansz let's discuss this at the next UI meeting and make sure we have a clear plan.