* Clean up Temperature PID
* Improve EEPROM read/write/validate
* Group `SINGLENOZZLE` saved settings
* Group planner saved settings
* Group filament change saved settings
* Group skew saved settings
* Group `FWRETRACT` saved settings

- Move FWRETRACT to the planner
- Combine leveling, skew, etc. in a single modifier method
- Have kinematic and non-kinematic moves call one planner method

* Fix G29 (ABL) retry behavior

See https://github.com/MarlinFirmware/Marlin/issues/5597#issuecomment-397683325

Use macros that explicitly avoid double-evaluation and can be used for any datatype, replacing `min`, `max`, `abs`, `fabs`, `labs`, and `FABS`.

Co-Authored-By: ejtagle <ejtagle@hotmail.com>

Co-Authored-By: ejtagle <ejtagle@hotmail.com>

Co-Authored-By: ManuelMcLure <manuelmclure@users.noreply.github.com>

Addressing #10538

Fix #10390

Fixes #10137

Some probes don't work near the edges of the bed. This change promotes MIN_PROBE_EDGE to a general setting that applies to all probing functions.

Some "fix-mounted" probes need manual stowing. And after probing some may prefer to raise or lower the nozzle. This restores an old option but tailors it to allow raise or lower as preferred.

Easier to configure. Catch an odd divisor.

* Fix G26 Circles...