Fix things in getPixel function

[petitssoldats]

Allow arguments of getPixel() equal to bound and ensure that arguments x & y are rounded

[arian]

Agree on the bounds.. but why should x and y be rounded?

[petitssoldats]

Without that, when i want to getPixel of

{x: 182.5, y: 125}

i get in return :

[undefined, undefined, undefined, 255 ]

Because the pixels array have rounded index. Am i right ?

[petitssoldats]

So ?

[LoganDark]

Round what you pass to getPixel...

Basically, give the function what it expects and you will get what you expect from it.