- add 2-way thSIce vars exchange to allow to use seaice dynamics in OCN; - rename:   fracIce     -> sIceFrac_cpl (<- match coupler var name)
- add 2-way thSIce vars exchange to allow to use seaice dynamics in OCN;
- rename:   fracIce     -> sIceFrac_cpl (<- match coupler var name)

altMITgcm/MITgcm66h,altMITgcm/MITgcm66h,altMITgcm/MITgcm66h,altMITgcm/MITgcm66h,altMITgcm/MITgcm66h,altMITgcm/MITgcm66h,altMITgcm/MITgcm66h,altMITgcm/MITgcm66h