Provide % complete slider for checklist items on Boards

[#1]

Description -

Why is this feature important to you - as others view the Board and the various Cards aligned they would be able to tell how far someone has gotten on any card and subsequent checklist items

How would you like the feature to work - similar to the Agile board which has the % complete slider available

Current Behaviour -  you can provide a due date for your individual checklist items but no indicator where you might be regarding that checklist item