MKPolylineView lineWidth should zoom

[LucasDeVil]

Hi there,

I encountered an issue I'm unable to fix...
I'd like to have the line width of an MKPolylineView to scale according to the map zoom.
So the larger I zoom the map the thicker the line should get.

Example: I have a track between 2 CLLocations which is 11m long. I want to set the width of this track to 11m and draw this track on the map.

Now this track should be shown as a kind of a square, since its width is as big as its length.
When I'm zooming the lines length will grow and the line width should grow, too.
But it doesn't.

How am I able to implement this behaviour?
Since there is no -(void)drawMapRect:(MKMapRect)mapRect zoomScale:(MKZoomScale)zoomScale inContext:(CGContextRef)context as mentioned in the documentation for MKMapKit I have no clue how to handle this.
(please take issue #19 for reference)