:bug: fix incorrect bounding box computation
:bug: fix incorrect bounding box computation

I now consider the shape to be a polygon2d from which some
transformations can be applied (like rotation & translation), and
finally can be converted into a bounding box for AABB collision checks.

Signed-off-by: Chris Camel <f7d69a896c9ea808d2bad017ca5719dd54190169@gmail.com>

ccamel/playground-elm,ccamel/playground-elm,ccamel/playground-elm