Update example scene to produce undistorted distance metrics

V-REP models vision sensors’ fields of vision as frusta – i.e., V-REP
assumes the camera’s field of view terminates in a plane whose points
are generally not equidistant from the aperture.  Unfortunately, most
humans think of a camera’s field of view terminating in a paraboloid.
Thus, to the human brain, the raw depth buffer V-REP returns appears
distorted.  This commit fixes that by getting depth data from a filter,
rather than the raw depth buffer; this causes V-REP to perform
correction on the data.
Correct documentation and example for 'simExtAutomobileRequestNoise'

The documentation string (and README documentation) for
'simExtAutomobileRequestNoise' specified that distance noise was passed
before intensity noise.  In actuality, the reverse is true.

This is an API-compatible change; only the documentation and example
have been updated.