Ammended UBlox driver to record SV Info, satelites_visible == satelites used. Info is recorded for all SVs, used or not. Might be useful for GPS debugging.
Merge branch 'master' into gps_fix
Some cleanup of NAV_SVINFO message handler
Merge branch 'master' of https://github.com/PX4/Firmware into gps_fix
Merged GPS info fixes from pigeonhunter