Added function for loading arrays

* Created loadArray function, which swaps arrays into spriteArray, then
edits the height and width of the canvas to match the sprite.
* Added second paragraph and an unordered list of images, to use as the
sprite selector.
* Added event listeners to the image elements.
* Did a little DRYing out of the copyArrayToCanvas() function.

To do:
* The sprite swapper still isn’t working — need to fix it.
* Add unit tests in Jasmine.
Fixed "mac" matrix

* Matrix was missing two arrays on line 14, causing an exception to be
thrown.
* Renamed instances of “array” to “matrix” for clarity.
* Removed var declaration and if statements from loadMatrix(), since
they were superfluous.
* Added license. (ISC)
querySelector for click events now getElementById
Fixed canvas height/width bug
Fixed pocketwatch matrix
Wrapped div around canvas
Merge branch 'sprite-swapper'