Show image and updated time in status page

Summary: This lets us show more information about the locations on the status page.

Test Plan:
Load dagit in docker directory (where there are images), view image column and updated column
Load dagit in environment with no images, image column is blank (I think that is OK?)

Reviewers: dish

Reviewed By: dish

Differential Revision: https://dagster.phacility.com/D7974