Oxygen units

[denispauline]

[Comment from Kenny]

Oxygen units were listed as ml/L, I assume this is supposed to be mg/L and is a typo, but just want to make sure.

[acapet]

I confirm the default units in ICES standard is ml/l which is simply mmol/m3 / 44.66
We'll stick with that unit for the validation table and the station files.