Default state on trade should show placeholder text

[reallybeard]

Overview

When the trade widget/page is first loaded it currently shows 0 it should instead show placeholder text 0.00 or $0.00 if in fiat.

References and additional details

This is for the trade component

Acceptance Criteria

Show the placeholder value until the user has input a value or hit max button.

Need By Date

No response

Screenshots/Mockups

Estimated effort

No response