ENH: Add SimpleITK IO plugin.

IO plugin for SimpleITK, http://simpleitk.org/

imread and imsave implemented. Tests based off the PIL tests.

skimage/io/_plugins/simpleitk_plugin.py

@@ -0,0 +1,21 @@
+__all__ = ['imread', 'imsave']
+
+try:
+    import SimpleITK as sitk
+except ImportError:
+    raise ImportError("SimpleITK could not be found. "
+                      "Please try "
+                      "  easy_install SimpleITK "
+                      "or refer to "
+                      "  http://simpleitk.org/ "
+                      "for further instructions.")
+
+
+def imread(fname):
+    sitk_img = sitk.ReadImage(fname)
+    return sitk.GetArrayFromImage(sitk_img)
+
+
+def imsave(fname, arr):
+    sitk_img = sitk.GetImageFromArray(arr, isVector=True)
+    sitk.WriteImage(sitk_img, fname)