Ocean fluxes for the coupler

[einola]

When coupling with the ocean, the coupler expects to send the following to the ocean

• Ice-ocean and atmosphere-ocean stresses (x, y, and norm)
• Fresh-water flux
• Non-solar heat flux
• Short-wave flux at the ocean surface
• Salt flux
• Ice concentration

These need addressing as

• Ice-ocean stress is handled by Get the ice-ocean stress into the ModelArrayRef system #655, but the atmosphere-ocean stress is not calculated, and the stresses must be merged
• The fresh-water flux is not explicitly calculated
• The non-solar heat flux is not explicitly calculated
• The short-wave flux at the ocean surface is not explicitly calculated
• The salt flux is not explicitly calculated

In addition, the slab ocean uses an implicit salt change calculation, but

• The slab ocean should use pre-calculated fresh-water and salt fluxes to calculate the change in SSS