Merge pull request #7 from nasa/3-fix_ray_tracer

#6 fix ray tracer

bug fix in visible feature finder

minor bug fix in SFN pnp ransac iterations

release to fix some SFN bug fixes

This version should enable SFN to work fully (along with the other re…

…lnav, sopnav, and calibration techniques)

Minor bug fixes and a couple performance improvements from version 1.0.0

The first version of GIANT for public release