Update chipmunk example to fix some minor differences between it and stable (particularly those two that were just introduced)
Update chipmunk example to fix some minor differences between it and stable (particularly those two that were just introduced)

JacquesCarette/literate-scientific-software,JacquesCarette/literate-scientific-software,JacquesCarette/literate-scientific-software,JacquesCarette/literate-scientific-software,JacquesCarette/literate-scientific-software,JacquesCarette/literate-scientific-software,JacquesCarette/literate-scientific-software