add a function to draw lens on a pil.Image
Merge branch 'master' of github.com:Sorrow17/workspace
half finished lens light
Merge pull request #6 from Sorrow17/master

Add a function called "draw_lens_on"
Merge pull request #7 from OnlineOpticLaboratory/master

Merge pull request #2 from menghuan007/master
Merge pull request #3 from menghuan007/master

111