instead of point.

include a pixel multiple times in the output lists.

upper threshold.  This changes the function's API.

rectangle.

threshold_image().

object_detector constructor from python.  So now you can pack multiple
detectors into one object via the python API.

image_window in Python.

integer radius. Also made the circles centered on the center of the pixel at
their center when you zoom in.

norm regularization stuff to Python. This also includes adding
num_separable_filters() and threshold_filter_singular_values() to the Python API.