Add "Pan/Zoom" state to default options for capture

[BigRoy]

Discussion

The CameraOptions to not, by default, assign default values to the camera's pan/scan settings, also described here: Colorbleed/maya-capture-gui#66

Should we implement a default for this?

Note that it is already possible to supply the options to customize it with capture.capture. For example:

import capture

# No pan/zoom
capture.capture(camera="persp", camera_options={"panZoomEnabled": 0, "horizontalPan": 0.0, "verticalPan": 0.0, "zoom": 1.0})

# Pan/zoom with 0.2 horizontal pan
capture.capture(camera="persp", camera_options={"panZoomEnabled": 1, "horizontalPan": 0.2, "verticalPan": 0.0, "zoom": 1.0})