Re-ARM has been tested.  AVR has not been tested.

1) moved all cpu specific items to files in the low level HAL directory
for that CPU (pinDebug_Re-ARM.h & pinsDebug_AVR_8_bit.h

2) added pinsDebug.h to the top level directory

3) modified HAL_pinsDebug.h to select the correct support file for the
selected CPU

4) Patched sanitycheck to stop throwing false errors.  A long term
solution will be done

5) misc changes & bug fixes
arduino.cpp - included macros.h to fix a missing definition
pinmap_re-arm.h - removed a duplicated line.
pinmapping.h - changed from "ENABLED" to "defined" to fix a compile
error

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split SanityCheck up, improve pinsDebug system

======================================================================

switch to latest pins_RAMPS_RE_ARM.h

Implement AVR Platform

According to LinuxCNC, G5 should throw an error if the current plane mode isn't XY.

* Add Max7219 LED Matrix Debug Support

The Max7219 8x8 LED Matrix's are very helpful for debugging new code.
And for that matter, just trying to maximize printer settings without
causing stuttering.

The displays are very inexpensive (under $2.00 with shipping) and
provide a lot of help when trying to debug complicated code.

* Try to keep Makefile up to date.

When M405 is used it changes 'volumetric_multiplier[FILAMENT_SENSOR_EXTRUDER_NUM]' value. When M406 disables M405 it leaves the value unchanged.
This PR applies 'calculate_volumetric_multipliers' in M406 instead of resetting it to 1.0 because M200 may not be compatible with M405 hence I'm sure to restore anyway with correct value.

When switching noozle and extruder but these operations are done by the same servo in 'setup' function there is a unnecessary call

* Disallow filament change while paused

* Use kinematic movemements in pause_print and resume_print

Axis would only move when homing.
Bug introduced in 91841d75c9.
Fixes #6956, fixes #7050 and fixes #7291