Batch of various patches and tweaks 

Update to fix PCF_CHECK and also a typo 

Patch to restore CHOME macro for legacy compatibility 

Simplify configuration structure, reimplement some macros, and update… … inline documentation

Simplify configuration structure and reimplement some macros 

Limit max pcf fan speed for safety 

Lower holding current for steppers 

Minor changes for base cooling and reporting 

Update preheat presets 

Merge pull request #1 from smiksky/main - **Remove debug LED override** Remove `pcb_LED` override of bootloader's debug LED - **Remove duplicate virtual_sd definition** Virtual SD is already declared in fluid.cfg and explicit path declaration here produces difficult to diagnose errors if installed under other users