Status spinners

[travisjupp]

Media component missing spinners on modals

[travisjupp]

Vertically align Post components' spinners; currently displaying at the top of the viewport.

Possibly wrap in a div that's the vertical height of a users visible screen area.

Units: 100vh or % ?

[travisjupp]

To properly center the spinner, subtract height of the nav-bar from the viewport height. Currently it renders just below the center of the page.