The gpssim code was named gps_sim vs being consistent with other
simulators (gpssim). It also used warnx and errx and had lots of
commeted out code.
Signed-off-by: Mark Charlebois <charlebm@gmail.com>
Changed rc.S to rcS.
Updated README.md to explain the require directory structure and
where to run mainapp from for SITL to work correctly.
Signed-off-by: Mark Charlebois <charlebm@gmail.com>