Run the Janelia / HHMI Cellmap Segmentation Challenge

[yuvipanda]

Follow-on from #162, for running the actual challenge for a year.

Contract that justifies this ongoing service:

Definition of done

• Challenge is completed, winners are announced

[Gman0909]

@yuvipanda do you feel this issue can be closed now all sub-tasks have been completed?

[yuvipanda]

@Gman0909 this is an ongoing service we're responsible for until the end of the year, and I've put that in 'ongoing services' in the board for that reason. so i say we keep this open until it's done?