Temporary local override of NavigatedDisplay. [1512]

This commit merely adds this class to the McIDAS-V repository. This
file may be removed once Unidata accept pull request #40.
Rename NavigatedDisplay.rotate* fields. [1512]

rotateX, rotateY, and rotateZ are now rotateXMultiplier,
rotateYMultiplier, and rotateZMultiplier…and the
setRotationMultiplierMatrix() and rotate() methods have been updated to
use the new field names.

Again, remove this once Unidata accepts pull request #40 (assuming they
do, of course).