get_drivers: matrix for holding driver data
In robertladwig/thermod: Simplified lake model in R

matrix for holding driver data

get_drivers(
  drivers_df,
  model_dates,
  n_drivers,
  driver_colnames,
  driver_cv,
  n_step,
  n_en
)

`drivers_df`	dataframe which holds all the driver data
`model_dates`	dates for model run
`n_drivers`	number of model drivers
`driver_colnames`	column names of the drivers in the driver dataframe
`driver_cv`	coefficient of variation for each driver data
`n_step`	number of model timesteps
`n_en`	number of ensembles