This commit forward ports the changes made for 0.6.17, in order to store
the type and sensitive flag against outputs.
It also refactors the logic of the import for V0 to V1 state, and
fixes up the call sites of the new format for outputs in V2 state.
Finally we fix up tests which did not previously set a state version
where one is required.
This commit rectifies the fact that the original binary state is
referred to as V1 in the source code, but the first version of the JSON
state uses StateVersion: 1. We instead make the code refer to V0 as the
binary state, and V1 as the first version of JSON state.