waterOptions: Global options for water package
In midraed/water: Actual Evapotranspiration with Energy Balance Models

This function is based on raster::rasterOptions by Robert Hijmans.

waterOptions(
  overwrite,
  writeResults,
  outputFolder,
  SRTMrepo,
  autoAoi,
  default = FALSE
)

`overwrite`	Logical. If TRUE and writeResults is TRUE it will overwrite results. If FALSE, results are save with a name with name_datetime.
`writeResults`	Logical. If TRUE it'll write result to disk. This is slower but if FALSE you can have out-of-memory problems.
`outputFolder`	Name of a folder to save files, relative to workind folder.
`SRTMrepo`	A folder where SRTM grids are stored, to create DEM. See prepareSRTMdata()
`autoAoi`	Logical. If TRUE it'll look for a object called aoi on .GlobalEnv and use it as aoi. See createAoi()
`default`	Logical. If TRUE will revert all options to defaults values