fix: switch top and left arguments in createRect() call, fixes #1

[jankohlbach]

as proposed in #1 (comment)

[lesnitsky]

readme diff looks a bit weird
are you sure it is correct? :)

[jankohlbach]

yeah, I think that's because of that git tutor stuff, don't really know how that works :/
that's stupid, it's more visible in diff side by side mode, nothing really changed, but I think git marks the + and - as changes ...