Tying to fix initialization that is occuring when switched into REL_NAV
flight mode.
Fixed RelNAV.h to use DBG->print instead of Serial1 which competes with GPS
outside HIL mode.
Fixed problem of trying to print to NULL serial object pointer.
Fixed problem of trying to print to NULL serial object pointer.
Merge branch 'Fix_Initializing' of https://github.com/mdarling39/Arduino_Follower into Fix_Initializing
Added MAVLINK message to update status Pose estimate status
Fixed bug to enable navigation with vision data regardless of GPS lock.

Had to assign the "have_position" global variable to equal "have_rnav" so
that the navigation loop would be entered. (By default, the code does not
execute if "have_rnav" is false to prevent navigating with corrupt data)