Fixed 'bottomleft', 'bottomright' and 'topright' in Rect.prototypes
objects.accessors() to work as expected. They used some parameters from
normalizeRectArguments that don't exist, like 'bottom' and 'right'.
Now the values are set correctly from the given arguments.
Merge pull request #63 from weeezes/master

Rect's 'bottomleft', 'bottomright' and 'topright' sets fixed