Show the sharing div only when it is in Turtle and the solution is passing.
Merge pull request #356 from nanan9177/sharing

Only showing the student drawings.
Bump version to 0.0.141
Moving the test to turtle in turtle.js.
Merge pull request #355 from nanan9177/sharing_pic

Show the sharing div only when it is in Turtle and the solution is passi...
Greatly increase acceptable error on alpha opacity to deal with imperfect implementations.
Add comment.
Merge pull request #360 from tobyk100/fix-alpha

Greatly increase acceptable error on alpha opacity to deal with imperfec...
Bump version to 0.0.142
Added grey border around the drawing.