Maintenance for vtkCameraOrientationWidget

@mwestphal, @utkarsh.ayachit please take a look at this maintenance commit for the vtkCameraOrienationWidget and its representation.

• Update incorrect documentation for the representation. The previous docstring is a shameless copy-pasta I did from vtkPVAxesWidget when I wrote this class.
• Did some code maintenance to comply with a few clang-tidy complaints.
• Fix the over-responsiveness of this widget by responding to mouse clicks only if a handle was selected.
• Fix glitchy behavior where the widget flips direction after rotating it and clicking in an empty area immediately after rotating.