Extension of M221, Tune menu

Firmware retraction now stores the retract and recover speeds in mm/s
instead of mm/min. This makes it match the units of the maximum
feedrate, and fixes problems with modifying the value via LCD control
panel. From gcode, the values are still taken in mm/min to match the
units of G1 and similar, and they are converted to mm/s before they are
stored.

I also lowered the default retract feedrate to make it less likely to
cause problems for geared extruders when the user hasn’t bothered to
set a reasonable maximum feedrate, though users should be setting both
of these values to suit their hardware.

Signed-off-by: Matthew Schick <matthew.schick@gmail.com>

Added CHDK support to take pictures instead of doing an IR command, see more about how to use it here http://captain-slow.dk/2014/03/09/3d-printing-timelapses/

Added so M240 can be used to trigger CHDK instead of sending an IR signal, see more about CHDK here http://captain-slow.dk/2014/03/09/3d-printing-timelapses/

Increase Z_HOME_RETRACT_MM to 2mm default to avoid end stop not switching during retract.

- Fixed Few finnish transalations
- Removed duplicate contrast define

I made these changes previously, but I can’t find the commit now. This
reapplies the changes to get auto retract working again.

Conflicts:
	Marlin/Configuration_adv.h
	Marlin/Marlin_main.cpp

Users can be confused as to which values to enter after a PID tune. Updating the message to help clarity it.
New message: "PID Autotune finished! Put the last Kp, Ki and Kd constants from above into Configuration.h"

Old message: "PID Autotune finished! Put the Kp, Ki and Kd constants into Configuration.h"

Fixed compiler errors on Ubuntu using arduino-core

If position is unknown, then G29 can be dangerous.

This reverts commit 51ae4881ab.

Save above configs in eeprom
fix docs in createTemperatureLookupMarlin.py
add missing azteegX3pro digipot settings in delta example config

This should make it safe to enable FWRETRACT by default, with
autoretract (which should now be fixed) only enabled by M209. FWRETRACT
should probably now default to enabled (to make G10/G11 and M207-209
available, without changing functionality when they are not used), but
I’ll save that for another pull request/discussion.

This takes the (now working) G10/G11 code and moves it to a function,
which is called by G10 and G11, and also called by G1 if autoretract is
enabled and a retract/recover move is detected.