Color circle detection: update

EL: Changes to test_circles_yan.py: Slight tweaking from testing.  18 images tested. Results:
12 images completely correct: 
(2,0,0): 2 images with 0 color circles had 0 color circles detected
(10,3,3): 2 images with 3 color circles had 3 color circles (blue and red in both cases) detected
Missing color circles:
(1,3,0): 1 image with 3 color circles had 0 color circle detected
(2,3,2): 2 images with 3 color circles had 2 color circles detected (blue and red in both cases) 
False detection:
(1,0,1): 1 image with 0 color circles had 1 color circle detected
(2,3,4): 2 images with 3 color circles had 4 color circle detected