ENH: Use nearest neighbor interpolation by default in matplotlib plugin.

skimage/io/_plugins/matplotlib_plugin.py

@@ -1,4 +1,11 @@
-from matplotlib.pyplot import imshow, show, imread
+import matplotlib.pyplot as plt
+
+def imshow(*args, **kwargs):
+    kwargs.setdefault('interpolation', 'nearest')
+    plt.imshow(*args, **kwargs)
+
+imread = plt.imread
+show = plt.show
 
 def _app_show():
     show()