Handle validation errors for work order card on planning board and details

DMO-976

Validation errors on a planning board draft are now more visible to the planner, so that any possible action to clear the error can be taken before trying to send in the draft:

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!image-20200818-065452 (f9bfdc07-d8ed-44e4-be1e-1caf91f36d96).png|width=558,height=810!

There is both visible information on the planning board grid and detailed information when opening details for the individual schedule or work order.