Renaming public variables

[nmizukami]

These variables are exposed to users through control file. if their names are not very intuitive, consider renaming

! DIRECTORIES
ancil_dir            = ''              ! directory containing ancillary data
input_dir            = ''              ! directory containing input data
output_dir           = ''              ! directory containing output data
restart_dir          = charMissing     ! directory for restart output (netCDF)

! RUN CONTROL
case_name            = ''              ! name of simulation
continue_run         = .false.         ! T-> append output in existing history files. F-> write output in new history file
simStart             = ''              ! date string defining the start of the simulation
simEnd               = ''              ! date string defining the end of the simulation
newFileFrequency     = 'annual'        ! frequency for new output files (day, month, annual, single)
routOpt              = '0'             ! routing scheme options  0: accum runoff, 1:IRF, 2:KWT, 3:KW, 4:MC, 5:DW
doesBasinRoute       = 1               ! basin routing options   0-> no, 1->IRF, otherwise error
is_lake_sim          = .false.           ! logical if lakes are activated in simulation
lake_model_D03       = .false.     ! logical if Doll 2003 model is used, specify as 1 in lake_model_type in network topology
lake_model_H06       = .false.     ! logical if Hanasaki 2006 model is used, specify as 2 in lake_model_type in network topology
lake_model_HYPE      = .false.         ! logical if HYPE model is used, specify as 3 in lake_model_type in network topology
is_flux_wm           = .false.         ! logical if flow is added or removed from a reach
is_vol_wm            = .false.         ! logical if target volume is considered for a lake
is_vol_wm_jumpstart  = .false.         ! logical if true the volume is reset to target volume for the first time step of modeling
suppress_runoff      = .false.         ! logical to suppress the read runoff to zero(0)
suppress_P_Ep        = .false.         ! logical to suppress evaporation and precipitation to zero(0)
 
! RIVER NETWORK TOPOLOGY
fname_ntopOld        = ''              ! old filename containing stream network topology information
ntopAugmentMode      = .false.    ! option for river network augmentation mode. terminate the program after writing augmented ntopo.
fname_ntopNew        = ''              ! new filename containing stream network topology information
dname_sseg           = ''              ! dimension name of segment in river network data
dname_nhru           = ''              ! dimension name of hru in river network data
idSegOut             = integerMissing  ! id of outlet stream segment

! RUNOFF, EVAPORATION AND PRECIPITATION FILE
fname_qsim           = ''              ! simulated runoff netCDF name
vname_qsim           = ''              ! variable name for simulated runoff
vname_evapo          = ''              ! variable name for actual evapoartion
vname_precip         = ''              ! variable name for precipitation
vname_time           = ''              ! variable name for time
vname_hruid          = ''              ! variable name for runoff hru id
dname_time           = ''              ! dimension name for time
dname_hruid          = ''              ! dimension name for hru in runoff data
dname_xlon           = ''              ! dimension name for x (j, longitude) dimension
dname_ylat           = ''              ! dimension name for y (i, latitude) dimension
units_qsim           = ''              ! units of simulated runoff data
dt                   = realMissing     ! time step (seconds)
input_fillvalue      = realMissing     ! fillvalue used for input variables (runoff, precipitation, evaporation)
 
! FLUXES TO/FROM REACHES AND LAKES STATES FILE
fname_wm             = ''          ! the txt file name that includes nc files holesing the abstraction, injection, target volume values
vname_flux_wm        = ''              ! variable name for abstraction or injection from or to a river segment
vname_vol_wm         = ''              ! variable name for target volume when lake is_lake_sim is on
vname_time_wm        = ''              ! variable name for time
vname_segid_wm       = ''              ! variable name for runoff hru id
dname_time_wm        = ''              ! dimension name for time
dname_segid_wm       = ''              ! dimension name for hru in runoff data

! RUNOFF REMAPPING
is_remap             = .false.         ! logical whether or not runnoff needs to be mapped to river network HRU
fname_remap          = ''              ! runoff mapping netCDF name
vname_hruid_in_remap = ''              ! variable name for river network hru id
vname_weight         = ''              ! variable name for areal weights of runoff HRUs within each river network
vname_qhruid         = ''              ! variable name for runoff HRU ID
vname_num_qhru       = ''              ! variable for numbers of runoff HRUs within each river network HRU
vname_i_index        = ''              ! variable for numbers of y (latitude) index if runoff file is grid
vname_j_index        = ''              ! variable for numbers of x (longitude) index if runoff file is grid
dname_hru_remap      = ''              ! dimension name for river network HRU
dname_data_remap     = ''              ! dimension name for runoff HRU ID

! RESTART OPTION
restart_write        = 'never'         ! restart write option: N[n]ever-> never write, L[l]ast -> write at last time step, S[s]pecified, Monthly, Daily
restart_date         = charMissing     ! specifed restart date
restart_month        = 1               ! restart periodic month. Default Jan (write every January of year)
restart_day          = 1               ! restart periodic day.   Default 1st (write every 1st of month)
restart_hour         = 0               ! restart periodic hour.  Default 0hr (write every 00 hr of day)
fname_state_in       = charMissing     ! name of state file

! SPATIAL CONSTANT PARAMETERS
param_nml            = ''              ! name of the namelist file

! GAUGE METADATA
gageMetaFile         = charMissing     ! name of the gauge metadata csv
gageOutput           = .false.         ! logical; T-> history file output at only gauge points

! COMPUTATION OPTION
hydGeometryOption    = compute         ! option for hydraulic geometry calculations (0=read from file, 1=compute)
topoNetworkOption    = compute         ! option for network topology calculations (0=read from file, 1=compute)
computeReachList     = compute         ! option to compute list of upstream reaches (0=do not compute, 1=compute)

! TIME
time_units           = charMissing     ! time units time units. format should be <unit> since yyyy-mm-dd (hh:mm:ss). () can be omitted
calendar             = charMissing     ! calendar name
 
! MISCELLANEOUS
debug                = .false.         ! print out detaled information
desireId             = integerMissing  ! turn off checks or speficy reach ID if necessary to print on screen
  
! PFAFCODE
maxPfafLen           = 32              ! maximum digit of pfafstetter code (default 32).
pfafMissing          = '0'             ! missing pfafcode (e.g., reach without any upstream area)

Originally posted by @nmizukami in #288 (comment)