Update SimpleCV/Camera.py

extend the max number of AVT cameras to 100
SIFT KeyPoint Matching
docs added
print p?
Merge pull request #276 from jayrambhia/sift_keypoint_match

Sift keypoint match
This still needs tests, but I want to get these changes into develop tonight
Merge branch 'develop' of github.com:ingenuitas/SimpleCV into feature/MoreLineScan