Fix misuse of note box markup

This information needs to be emphasized as important, not marked as an
aside that many readers can skip.  Also fixed some passive voice that's
clearer as active voice.

Author: amartini51

TSPL.docc/LanguageGuide/Enumerations.md

@@ -549,16 +549,17 @@ Raw values can be
 strings, characters, or any of the integer or floating-point number types.
 Each raw value must be unique within its enumeration declaration.
 
-<!-- XXX fix this note box abuse; this is important, not optional -->
-
-> Note: Raw values are *not* the same as associated values.
-> Raw values are set to prepopulated values
-> when you first define the enumeration in your code,
-> like the three ASCII codes above.
-> The raw value for a particular enumeration case is always the same.
-> Associated values are set when you create a new constant or variable
-> based on one of the enumeration's cases,
-> and can be different each time you do so.
+Although you can use both raw values and associated values
+to give an enumeration an additional value,
+it's important to understand the difference between them.
+You pick the raw value for an enumeration case
+when you define that enumeration case in your code,
+like the three ASCII codes above.
+The raw value for a particular enumeration case is always the same.
+In contrast,
+you pick associated values when you create a new constant or variable
+using one of the enumeration's cases,
+and you can pick a different value each time you do so.
 
 ### Implicitly Assigned Raw Values