Default to not rescale coordinates in Linear/Cubic (#391)

Rescaling can have problems and generate unintended outputs. Since Scipy
defaults to not rescaling, let's do that here as well.

doc/gallery_src/cubic_gridder.py

@@ -87,5 +87,5 @@
 ax.plot(*coordinates, ".k", markersize=0.1, transform=crs)
 # Use an utility function to setup the tick labels and the land feature
 vd.datasets.setup_baja_bathymetry_map(ax)
-ax.set_title("Linear gridding of bathymetry")
+ax.set_title("Cubic gridding of bathymetry")
 plt.show()

verde/scipygridder.py

@@ -124,7 +124,7 @@ class Linear(_BaseScipyGridder):
     rescale : bool
         If ``True``, rescale the data coordinates to [0, 1] range before
         interpolation. Useful when coordinates vary greatly in scale. Default
-        is ``True``.
+        is ``False``.
 
     Attributes
     ----------
@@ -137,7 +137,7 @@ class Linear(_BaseScipyGridder):
 
     """
 
-    def __init__(self, rescale=True):
+    def __init__(self, rescale=False):
         super().__init__()
         self.rescale = rescale
 
@@ -161,7 +161,7 @@ class Cubic(_BaseScipyGridder):
     rescale : bool
         If ``True``, rescale the data coordinates to [0, 1] range before
         interpolation. Useful when coordinates vary greatly in scale. Default
-        is ``True``.
+        is ``False``.
 
     Attributes
     ----------
@@ -174,7 +174,7 @@ class Cubic(_BaseScipyGridder):
 
     """
 
-    def __init__(self, rescale=True):
+    def __init__(self, rescale=False):
         super().__init__()
         self.rescale = rescale