Disabled by default, so that logs are not deleted unexpectedly.

Allowing for easier access to SITL logs.

Reduces CPU load from ~6.9% to 5.3% (tested on Pixracer & Pixhawk). The
method is only used once, so it does not increase flash usage.

Remove old log directories on startup if free space falls below a threshold.
The threshold is 300MB or 10% of the disk capacity if that's smaller.

* Whitespace cleanup and add config for rplidar.

* Add rplidar target.

* Disable gps for rplidar.

DriverFramework has to be updated to update dspal to the
ATLFlight version of dspal.

Signed-off-by: Mark Charlebois <charlebm@gmail.com>

Navigator: Altitude acceptance to switch to new waypoints should be more accurace than horizontal distance by default

This patch ramps up the throttle to hover throttle instead of a fixed value and limits the vertical takeoff speed to the value set in the parameter. This should ensure smoother, slower takeoffs, in particular in autonomous flight modes.

Land detector: Since multicopters take off and land slower than 0.7 m/s, setting the default detection threshold to 0.5 m/s is a much safer default

* Fix build when px4 is a submodule

* Check if submodule directory exists.

* Fix submodule directory reading

   While the list was sorted, this change serialize the application
   of the patches.

   Moved the disply to the actual application of the patch not
   the configuration step.

* FMUv4pro : allow power monitoring for hipower rail

* FMUv4pro : init temperare calibration EEPROM CS

* FMUv4pro : workaround for safety switch

* FMUv4pro : remove useless and conflicting defines

* FMUv4pro : disable internal pull-up for OC sensing

/FAULT won't achieve VinputLow with internal pull-up resistor so it must
be turned off for both /VDD_5V_PERIPH_OC and /VDD_5V_HIPOWER_OC.
Replaced by external pull-up.

* FMUv4pro : correct safety switch handling

RC02 has a hardware pull-down on this signal

* Revert "FMUv4pro : workaround for safety switch"

This reverts commit 9528ae29b68700fa7c6604c1ac2756c7dac2819c.

   The recent changes to the timers increased memory by 8 bytes.
   and should have ONLY added 8 bytes
   was  20000dc0	40	20000E00
   is:  20000dc8	40	20000E08
   s/b  20000E08       1f3      next symbol

   But for some unknown reason the linker skipped to the next alignment
   of 256 and wasted 246 bytes.

   20000F00     1f3     next symbol

   Even with .align 8 in the .S file and . = ALIGN(4); in the linker
   script I could not move the allocation back only up to the next
   512 alighment.

   So this is a hack to shift things back 8 bytes.

* NSH Added support for set [{+|-}{e|x|xe|ex}] [<name> <value>]

   Set the 'exit on error control' and/or 'print a trace' of
   commands when parsing scripts in NSH.
   The settinngs are in effect from the point of exection,
   until they are changed again, or in the case of the init
   script, the settings are returned to the default settings
   when it exits.

   Included child scripts will run with the parents settings
   and changes made in the child script will effect the parent
   on return.

   Use 'set -e' to enable and 'set +e' to disable (ignore) the exit
   condition on commands. The default is -e. Errors cause script to
   exit.

   Use 'set -x' to enable and 'set +x' to disable (silence) printing
   a trace of the script commands as they are ececuted. The default
   is +x. No printing of a trace of script commands as they are
   executed.

  Print expanded variables if -x

* Added comments only on how to use the set +e and and set -x

* Spelling NSH_PFALG_* -> NSH_PFLAG_*