Map Retexturizer v19.1

• Fix material browser not showing previews when we click on the main folder
• Fix DataList:GetDifferences() not getting underflows and overflows
• Fix small time window where anti dyssync could run during a load
• Fix decal-editor not disabling borders while the Context Menu is open or when the decal was applied by the duplicator
• Fix Duplicator:LoadMaterials() not forcing positions correctly
• Fix GMod saves support not upgraded to the current codebase
• Fix duplicator generating fake error detections
• Fix DataList:CleanAll() not fully cleaning decal Data
• Fix toolgun not getting the current changed model material
• Fix tool could get stuck if duplicator failed
• Fix CustomMaterials:Create() applying data before storing the custom material
• Add fast validation check for custom materials
• Reenable locked anti dyssync systems after a full material cleanup
• Minor improvements