Further cleanup of UBL

Implement USE_CONTROLLER_FAN as a feature

Keep refreshing LCD if hotend status is on-screen

Fix BLTOUCH_HEATERS_OFF bug

UBL: G26 minor improvements 

General cleanup of G33

Fix Dual-Z endstop conditional test

- update comment section
- redefined P5 grid
- minor clean to probe radius routine
- updated EEPROM version to V37 according remark in #6517

Fix, cleanup, prettify `G29 O` output

Various leveling-related patches

* Fix Horizontal and Vertical optimization bug.

And drastically reduce the debug code foot print....

* Yeah Baby!

The debug print is going A - OK !