Add sigmao to observations and the possibility to set sigmao for observation sets. Sigmaos are relative to a normalized background error (1.0), so are in effect the epsilons directly.
NOTE: The observation sets in pseuodoobs in another PR must be adapted to this one when merged.
Add sigmao to observations and the possibility to set sigmao for observation sets. Sigmaos are relative to a normalized background error (1.0), so are in effect the epsilons directly.
NOTE: The observation sets in pseuodoobs in another PR must be adapted to this one when merged.