The compiler may be able to optimize if it knows an array won’t be
changing.

`gcode_M84` only needs to call `finishAndDisableSteppers`, which calls
all the other functions.

- Update prepare_move_delta to take a target argument
- Add Delta support to plan_arc

- Have `Servo::attach` explicitly return -1 if it fails
- Check for -1 in `Servo::move` because `servoIndex` might be 0
- Make `attach` / `detach` calls conditional on `SERVO_LEVELING`
- Move `SERVO_LEVELING` define to `Conditionals.h`

to make clear - it's not a question but an order.

and cleaned out some tabs.

Everything else is a rebased PR#2017 as proposed by @CptanPanic

by replacing the sequences (attach, write, delay, detach), and their conditions with the new function in Marlin.main.cpp
and removing the old configuration in the ABL part of Configuration.h

Sign flipped with #2167.
See also comments
https://github.com/MarlinFirmware/Marlin/issues/2040#issuecomment-118568355
and following.

- Also fix a bug in `M600` where `Z_MAX_ENDSTOP_INVERTING` is being
used as the index into the `destination[AxisEnum]` array.

here the other two occurences of `Z_PROBE_OFFSET_FROM_EXTRUDER` are
replaced with `zprobe_zoffset`.

verified via 1.0.2 tag that compiles by multiple people,
credit for the fix goes to paulusjacobus for the initial find and
sniffle for the correction so M851 works.

n_samples is an uint8_t .
Got printouts like:
50 of 2  ...

at least the lcd independent part from Marlin_main.cpp.

ZigZag has been disabled by fault due to do_topography_map

by:
Moving HAS_LCD_BUZZ macro to Coditionals.h
Renaming HAS_LCD_BUZZ to HAS_BUZZER to make clear is has nothing to do with the lcd.
Removing the ULTRALCD condition.

Moving declaration of lcd_buzz() out of the ULTRA_LCD block in ultralcd.h
Moving definition of lcd_buzz() out of the ULTIPANEL block in ultralcd.cpp
Renaming lcd_buzz() to buzz() to make clear is has nothing to do with the lcd.

All buzzing code is now only dependent on the existence of a BEEPER-pin or the definition of a LCD_USE_I2C_BUZZER.

To do: Check the conditions for the BEEPER-pin in all pin-files.

Now send only temperature for T or B, but not send OK.
Host interprets the line to show the right temperature, but not in
response to M105 then stop and send commands until it ends the autotune.

by avoiding the strncopy()

when DEFAULT_STEPPER_DEACTIVE_TIME is over
instead of simply turn off all.

More general solution to skip N[0-9]+[ ]* in the parser as in #2218

- When editing on the LCD, minus now means below the nozzle
- Stores the opposite sign in EEPROM, so bumped to “V20”