Refactor + Consolidate Button Components

[Nicholas-Chong]

Currently there are two separate components for regular/inverted buttons. Ideally we can consolidate Button.js and ButtonInverted.js into one component with the following interface/usage

Render a regular button (gradient background, white text):

<Button>
  Button text
</Button>

Render a Inverted Button (white background, gradient border, gradient text):

<Button inverted={true}>
  Button text
</Button>

[Nicholas-Chong]

@BryanGuan123 @SamuelCatania Apparently we can't assign multiple people to a ticket in GH bc we're using the free plan lol. I'm gonna pair you guys up on this one since its more complicated than the others :)