[Pharo-project] preferences to settings refactoring: #colorWhenPrettyPrinting case

Hi, A slice is upload in pharoInbox. Cheers Alain Name: SLICE-colorWhenPrettyPrintingRemoval-alain_plantec.2 Dependencies: Compiler-alain_plantec.104, Kernel-alain_plantec.renggli.335, KernelTests-alain_plantec.109, Polymorph-Tools-Diff-alain_plantec.21, System-FilePackage-alain_plantec.6, System-Support-alain_plantec.27, Tools-alain_plantec.154, Traits-alain_plantec.279 Remove the #colorWhenPrettyPrinting preference. As a consequence, some code formatting methods are refactored (The major remodelling is the Compiler>>#format:in:notifying:decorated: removal, replaced by Compiler>>#format:in:notifying:)