Exception: DateTime::__construct(): Failed to parse time string (0) at position 0 (0)

Problem/Motivation

Displays error when used on field with DateTime = 0

Steps to reproduce

1. Setup view of users
2. Add field User Last Login to view and set Formatter to Days ago
3. Add a user that has not logged in

Proposed resolution

Patch to check for 0 and set output to "Never"