Added utility to display the camera

This is based largely on the same utility in
obs_lsstSim.  Maybe we should make a camera
agnostic version of this, but I don't know
where it would go.
Fix imports

Removed unused imports and added an import for
shutil used but never imported.
Fixed bug in bounding boxes

There was on off by one error in the previous
version.  To fix this, check if there is a
prescan or overscan region.  Add a zero
extent bounding box if they do not exist.

Also switched to using extents.  I think
that's safer and easier to read.
Removed extra white space
New amp tables with fixed bboxes.
Response to review

Removed blank line in genCameraRepository.py
Made displayCamera.py executable.