Add operators ==, != and stream << to CameraPoint
Change CameraPoint.__repr__ as per Paul's request

It is not perfect because the repr for Point2D is not as he prefers.
I also added unit tests for repr of CameraPoint, CameraSys and CameraSysPrefix.
Merge branch 'tickets/DM-351'
Grow Footprints isotropically using RLE operations

This gives a roughly order of magnitude performance improvement over the
convolution with a circle used previously.
Use RLE for Manhattan Footprint dilation