[fixedwing][modules] make nav_cube a module
[fixewing][modules] convert nav_spiral to module
[fixedwing] convert disc_survey to module
[FIXEDWING] convert gls (gps landing) to a module
[fixedwing] convert nav_survey_rectangle to a module
[fixedwing] convert poly_survey_adv to a module
[fixedwing] convert border_line to a module
[fixedwing] nav_survey_rectangle back to subsystems
[fixedwing] convert nav_line to a module
[fixedwing] snav 'smooth navigation' as a module
[fixedwing] convert Osam navigation routines to a module. Common naming for start and run functions
[fixedwing][modules] clean advanced poly survey module
[fixedwing][modules] nav modules start and run functions
[conf] deprecate navigation type="extra" subsystem
[nav] remove old unused flight zone checking

now performed with sectors at compilation time
[nav] bomb has a nav module
[nav] match other modules function name for zamboni survey
[nav] split osam nav module
[nav] some functions should be static (line and survey OSAM)
[nav] trying to harmonize nav modules