Connected as described at http://printrbot.com/shop/led-strip/

Based on patch by Kelly Anderson <kelly@xilka.com> at
http://www.xilka.com/printrbot/marlin/1.1.4/20170707/

Probing with the effector in the printing area, but an eccentric probe (e.g. allen key) outside it but still touching the bed gives meaninfull information for calibration. Since calibration is most accurate when probing as close to the towers as possible the testing was way to restrictive hence this fix.

Add support for the PCA9632 PWM color LED driver used on the Ultimaker 2 and Wanhao Duplicator 6.

Changed UBL_G26_MESH_EDITING to UBL_G26_MESH_VALIDATION
Added UBL_MESH_EDIT_MOVES_Z to prepare for that change (coming next)

* Fix M48 for Delta's  There was a scope issue: DELTA_PROBEABLE_RADIUS wasn't getting defined.

* Check if the specified G29 command requires homing

 - rename to PROBING_HEATERS_OFF
 - move heater pausing functionality into thermalManager
   - add variables, pause(), ispaused(), other functions
 - add fan pausing functionality -> PROBING_FANS_OFF
 - add probing_pause() wrapper
 - move pausing into do_homing_move() and do_probe_move() to minimize quiet time and so other probe types can benefit
 - example configs

This is what I did yesterday:

- basicly gave the tests more comprehensive names; put all the
declarations at the top; got rid of the magic negative C-value (renamed
to P + A, O, T)

- "cos(RADIANS(180 + 30 * axis)) * (1 + circles * 0.1 * ((zig_zag) ? 1 :
-1)) * delta_calibration_radius" compiles wrong is zig_zag statement is
without brackets

- DELTA_TOWER_ANGLE_TRIM reset to 3 values (the calcs use the 3th value
to normalize will not compile otherwise)

-Wrote 3 dummies to keep EEPROM lenght the same

-Reset the configs to the 'original' with autocal + menu disabled (but
can be enabled of course)

The Configuration.h file entries for BL-Touch have been updated to:
```cpp
//#define BLTOUCH
//#define BLTOUCH_DELAY 375      // (ms) Enable and increase if needed
//#define BLTOUCH_HEATERS_OFF // if defined the printer's heaters are
turned off during probe event
```

More consistent with M665 where C-value is allowed as well, then
normalized

- Making M665 compatible with repetier (see
http://reprap.org/wiki/G_code#M665:_Set_delta_configuration)

- M665 B also sets the radius for manual calibration menu

- Converting tower ajustment definitions to arrays - tower angle
corrections compatible with Esher 3D wizzard

- Only tower angles need to be adjustable with M665 and stored to EEPROM
- tower radius and diag rod can be adjusted in the FW only with #define