Updated forcing.json for IAF after JRA55-do data copies deleted.

[aidanheerdegen]

Closes #36

[aidanheerdegen]

@nichannah I have updated checksum files and made a couple of other changes but the current test fail isn't something I feel comfortable just glossing over. It is at test_stubs.py:75

>       assert len(cur_exp_dts) == len(cur_forcing_dts) == \                                                            
                (len(forcing_update_dts) // len(field_names))                                                           
E       AssertionError: assert 8 == (9 // 2)                                                                            
E        +  where 8 = len([datetime.datetime(1900, 1, 1, 0, 0), datetime.datetime(1900, 1, 1, 3, 0), datetime.datetime(1
900, 1, 1, 6, 0), datetime.datetime(1900, 1, 1, 9, 0), datetime.datetime(1900, 1, 1, 12, 0), datetime.datetime(1900, 1, 
1, 15, 0), ...])                                                                                                        
E        +  and   9 = len([datetime.datetime(1900, 1, 1, 0, 0), datetime.datetime(1900, 1, 1, 0, 0), datetime.datetime(1
900, 1, 1, 3, 0), datetime.datetime(1900, 1, 1, 6, 0), datetime.datetime(1900, 1, 1, 9, 0), datetime.datetime(1900, 1, 1
, 12, 0), ...])                                                                                                         
E        +  and   2 = len(['swfld_ai', 'runof_ai'])                                                                     
                                                                                                                        
test_stubs.py:75: AssertionError                                                                                        
>>

Appears forcing_update_dts has an extra element, so is now length 9:

(Pdb) forcing_update_dts                                                                                                
[datetime.datetime(1900, 1, 1, 0, 0), datetime.datetime(1900, 1, 1, 0, 0), datetime.datetime(1900, 1, 1, 3, 0), datetime
.datetime(1900, 1, 1, 6, 0), datetime.datetime(1900, 1, 1, 9, 0), datetime.datetime(1900, 1, 1, 12, 0), datetime.datetim
e(1900, 1, 1, 15, 0), datetime.datetime(1900, 1, 1, 18, 0), datetime.datetime(1900, 1, 1, 21, 0)]

field_update_files also has 9 elements now

field_update_files
['/g/data/ua8/JRA55-do/RYF/v1-3/RYF.rsds.1990_1991.nc', '/g/data/ua8/JRA55-do/RYF/v1-3/RYF.runoff_all.1990_1991.nc', '/g
/data/ua8/JRA55-do/RYF/v1-3/RYF.rsds.1990_1991.nc', '/g/data/ua8/JRA55-do/RYF/v1-3/RYF.rsds.1990_1991.nc', '/g/data/ua8/
JRA55-do/RYF/v1-3/RYF.rsds.1990_1991.nc', '/g/data/ua8/JRA55-do/RYF/v1-3/RYF.rsds.1990_1991.nc', '/g/data/ua8/JRA55-do/R
YF/v1-3/RYF.rsds.1990_1991.nc', '/g/data/ua8/JRA55-do/RYF/v1-3/RYF.rsds.1990_1991.nc', '/g/data/ua8/JRA55-do/RYF/v1-3/RY
F.rsds.1990_1991.nc']