try, try again.

If 'OK' is garbled on sending PC won't receive it.  Both machines will
wait on each other forever.  This resends OK if nothing is heard from PC
for a while to avoid this bad case.

Borrow code from https://github.com/arduino/Arduino/issues/1793

The compiler does not support comparing float values: "error: floating constant in preprocessor expression"
The loss in X/Y precision shouldn't matter for Z probes, as most microswitches or inductive sensors are larger than 1mm square anyway.

The compiler does not support comparing float values: "error: floating constant in preprocessor expression"
The loss in X/Y precision shouldn't matter for Z probes, as most microswitches or inductive sensors are larger than 1mm square anyway.

Somehow the pin definitions for the MAX6675 Slave Select/Chip Select got changed back to the hardware SPI SS/CS.  
Pin 49 cannot be used as that is used by the SD card socket to detect if an SD card is present.
Pin 53 is the Hardware SPI SS, which is dedicated, nicely, to the SD card SS and therefore cannot be used as the MAX6675 SS
Pin 66 is in Aux2 port adjacent to the Hardware SPI interface port on RAMPS 1.4, and is currently not used for anything.

This fixes two regressions, caused by #1167 and #1191 .

sp=space-padded, similar to: ns=no-sign

This is the optimal code for a self-contained formatter, although the
original code is crafty in being smaller and simpler, and can be
evaluated as using the original output as a scratch pad for state,
making the final formatter more straightforward. While this code is
longer, all code-paths are minimal.

This is the optimal code for a self-contained formatter, although the
original code is crafty in being smaller and simpler, and can be
evaluated as using the original output as a scratch pad for state,
making the final formatter more straightforward. While this code is
longer, all code-paths are minimal.

Turn off by default.

No matter what LANGUAGE_CHOICE was set to it would always take the en branch.
I revamped it a bit to use a macro to create the language include file name. This required a slight tweak to the RU declaration since it's special-cased in a couple places in code.

This is an attempt to pull my changes from #1222 over.

To test/enable, uncomment the #define DELTA_CALIBRATION_MENU in Configuration.h

fixed minor typo

void manage_inactivity(bool ignore_stepper_queue=false)

standard is false so it is not necessary to change additional code. this
change should be better, hopefully nophead like this :)

more speaking name

make a more general solution

Tested for SAV MKI and SAV 3D LCD on lewihe.

- Fixed issue when BAL area probing is shorter than it should be for
grid probing
- Warning when BAL activated with Delta Kinematics
- Fix XY_TRAVEL_SPEED when homing Z axis

Current defaults are all 255.  If it makes sense to reduce them, they should come down together, and
be in a  PID_INTEGRAL_DRIVE_MAX <= PID_MAX <- BANG_MAX relationship.