Consider negative Z Offsets when auto bed leveling is active

Fixed BABYSTEPPING feature

Fixes #1069.  Added "auto fan" checks to PID_autotune.

 temperature.cpp: Add Conditional Integration to prevent excessive integral windup

Move initialization of errormagic[] and echomagic[] to Marlin_main.cpp

LCD Progress Bar

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.

getting even with v1

Moved PSTR() macro to correct place which was causing the " initializer fails to determine size of '__c' " when attempting to compile with BABYSTEPPING enabled.

Clarification and markdown for boelle notes

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.

Merge pull request #1213 from ErikZalm/Marlin_v1

Merge pull request #1214 from ErikZalm/Marlin_v1

added note about stale branches

added note about stale branches

Revert "Change Auto_Bed_Leveling to Auto_Bed_Compensation"

Use SdFatUtil::FreeRam() for freeMemory() if there

Split do_blocking_move() to XY and Z sections

Fix syntax errors in #ifdef

Change Auto_Bed_Leveling to Auto_Bed_Compensation

Changed level to compensation

Changed leveling to compensation

Changed level and leveling to compensation.

Changed level and leveling to compensation

Changed level and leveling to compensation (except with "verbose_level" and "lcd_reset_alert_level").

Changed AUTO_BED_LEVELING to AUTO_BED_COMPENSATION

Changed AUTO_BED_LEVELING to AUTO_BED_COMPENSATION

Changed AUTO_BED_LEVEL to AUTO_BED_COMPENSATION