cdrch

Removes the reference to a non-existent custom.js in the blockrectangles example. Fixes #62. (Unless the intent was to actually have other code?)

Fixes a problem introduced with the addition of fullscreen. Previously, the pointer placement had been incorrectly scaled due to the scale constantly resetting, which was caused by an incorrect call...

Fixes #72's typo in the sineCubed function. Note: removed accidental combination of multiple PRs. 😅