Added computation to get north up rotation from ground point.
Added computation to get north up rotation from ground point.

USGS-Astrogeology/ISIS3_scripts,thareUSGS/ISIS3_scripts,thareUSGS/ISIS3_scripts,USGS-Astrogeology/ISIS3_scripts,thareUSGS/ISIS3_scripts,USGS-Astrogeology/ISIS3_scripts,USGS-Astrogeology/ISIS3_scripts,thareUSGS/ISIS3_scripts