docs: Added the UseBuiltInNames option to README

Author: SolidAlloy

README.md

@@ -190,6 +190,10 @@ You can make the field show just the type name without its namespace. For exampl
 
    
 
+By default, the field shows built-in types by their keyword name instead of the full name (e.g. `int` instead of `System.Int32`). You can change this by setting the *UseBuiltInNames* option to false.
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 ## Inherits Attribute
 
 This attribute allows you to choose only from the classes that implement a certain interface or extend a class. It has all the arguments `TypeOptions` provides.