Plugins: Heightmap

It's a porting of image2gcode from LinuxCNC and another python implementation from scorch: dmap2gcode
It takes an image and creates a height pocketing using darkest area as deeper and lighter area as higher. Here is a fast test (bad quality):

From:

To:

or from this:

to this:

and this:

It needs PIL and try to use numpy if installed.