Merge pull request #276 from moneyadviceservice/advice_plan_command

Stub AdvicePlans::StartTaskCommand
Revert "Merge pull request #276 from moneyadviceservice/advice_plan_command"

This reverts commit 7e1916519e5bebc12621b185a2399a71693fcd86, reversing
changes made to 29964acc478e923493d2818c69f666a2f33bb831.
Revert "Revert "Merge pull request #276 from moneyadviceservice/advice_plan_command""

This reverts commit b952913e4c13257a134619f7ab924151bfd39559.
`AdvicePlans::StartTaskCommand' must be a Struct