Clean up and add example for C.32 - raw pointers (#1909)

* Update CppCoreGuidelines.md

* Update CppCoreGuidelines.md

* Update isocpp.dic

* use snake casing

* sake case naming

* C 32 comments (#3)

* F.16 ("in" parameters): Move Matrix example to F.20 (return values) (#1922)

The `Matrix` example and the notes about assignment appear off-topic in rule F.16, as F.16 is specifically about "in" parameters.

With help from Sergey Zubkov.

* SL.io.50 (Avoid `endl`): Mention string streams (#1920)

Explicitly mentioned string streams as `endl` insertions into string streams do actually occur in the wild.

With help from Sergey Zubkov.

* Extended E.16 to include copy ctor for exception type, closes #1921

* Fix GitHub Actions build warnings, Marker style should be `*` (#1925)

* restored reference

* Added references to note

Co-authored-by: Niels Dekker <N.Dekker@lumc.nl>
Co-authored-by: Herb Sutter <herb.sutter@gmail.com>

Co-authored-by: Niels Dekker <N.Dekker@lumc.nl>
Co-authored-by: Herb Sutter <herb.sutter@gmail.com>

CppCoreGuidelines.md

@@ -4993,12 +4993,19 @@ There is a lot of code that is non-specific about ownership.
 
 ##### Example
 
-    ???
+    class legacy_class
+    {
+        foo* m_owning;
+        bar* m_observer;
+    }
+
+The only way to determine ownership may be to dig through the code to look for
+allocations.  If a pointer or reference is owning, document it as owning.
 
 ##### Note
 
-If the `T*` or `T&` is owning, mark it `owning`. If the `T*` is not owning, consider marking it `ptr`.
-This will aid documentation and analysis.
+Ownership should be clear in new code (and refactored legacy code) according to [R.20](#Rr-owner) for owned
+pointers and [R.3](#Rr-ptr) for non-owned pointers.  References should never own [R.4](#Rr-ref).
 
 ##### Enforcement
 

scripts/hunspell/isocpp.dic

@@ -286,6 +286,7 @@ Lakos
 Lakos96
 Lavavej
 LCSD05
+legacy_class
 lifecycle
 *life-time
 linearization
@@ -301,6 +302,8 @@ lvalues
 m1
 m2
 m3
+m_owning;
+m_observer;
 macros2
 malloc
 mallocfree