use unity normalization; add error catch if more than one normalization type is specified

[DeniseWorthen]

Switch to using unityone normalization in ufs for all fields
Add model abort if more than one normalization type is specified for any n1:n2:maptype

CMEPs Issues:

#38
#40

Description of changes

• implements unity normalization by changing normalization type for all fields in esmFldsExchange_nems_mod.F90 from none to one
• adds error catch if more than one normalization type is specified for a given map type between two components. For example attempting to set the normalization of Sa_pslv to "none" in this branch produces the following error message in the PET logs.

20210415 123018.685 INFO             PET000  Map type consf, destcomp atm,  mapnorm ofrac  So_t
20210415 123018.685 INFO             PET000  Map type consf, destcomp atm,  mapnorm ifrac  Faii_evap
20210415 123018.687 INFO             PET000  Map type consf, destcomp ocn,  mapnorm one  Faxa_lat
20210415 123018.687 INFO             PET000  Map type consf, destcomp ocn,  mapnorm one set; cannot set mapnorm to none  Sa_pslv
20210415 123018.687 INFO             PET000 Finalizing ESMF