Analysis extent determined by DEM, not smaller of DEM and land cover

[CEKrause]

The wind multipliers code uses the extent of the DEM to clip the land cover dataset. If the land cover dataset is smaller than the DEM, the code will not clip the DEM to the overlapping area. Instead, you just end up with a whole lot of outputs with '1'.

It would be good to be able to determine which of the two datasets is smaller, and clip the extent based on that dataset.