Fixing up suggestions from Issues 505 and 496

Author: Andrew Pardoe

CppCoreGuidelines.md

@@ -57,6 +57,7 @@ Supporting sections:
 * [Appendix A: Libraries](#S-libraries)
 * [Appendix B: Modernizing code](#S-modernizing)
 * [Appendix C: Discussion](#S-discussion)
+* [Appendix D: Tools support](#S-tools)
 * [Glossary](#S-glossary)
 * [To-do: Unclassified proto-rules](#S-unclassified)
 
@@ -426,6 +427,7 @@ Supporting sections:
 * [Appendix A: Libraries](#S-libraries)
 * [Appendix B: Modernizing code](#S-modernizing)
 * [Appendix C: Discussion](#S-discussion)
+* [Appendix D: Tools support](#S-tools)
 * [Glossary](#S-glossary)
 * [To-do: Unclassified proto-rules](#S-unclassified)
 
@@ -2613,7 +2615,7 @@ Member functions defined in-class are `inline` by default.
 
 ##### Exception
 
-Template functions (incl. template member functions) must be in headers and therefore inline.
+Template functions (incl. template member functions) are normally defined in headers and therefore inline.
 
 ##### Enforcement
 
@@ -21140,6 +21142,20 @@ It is common to need an initial set of elements.
 
 When is a class a container? ???
 
+# <a name="S-tools"></a>Appendix D: Supporting tools
+
+This section contains a list of tools that directly support adoption of the C++ Core Guidelines. This list is not intended to be an exhaustive list of tools
+that are helpful in writing good C++ code. If a tool is designed specifically to support and links to the C++ Core Guidelines it is a candidate for inclusion.
+In particular, here we present further rationale, longer examples, and discussions of alternatives.
+
+### <a name="St-clangtidy"></a>Tools: [Clang-tidy](http://clang.llvm.org/extra/clang-tidy/checks/list.html)
+
+Clang-tidy has a set of rules that specifically enforce the C++ Core Guidelines. These rules are named in the pattern `cppcoreguidelines-*`.
+
+### <a name="St-cppcorecheck"></a>Tools: [CppCoreCheck](https://docs.microsoft.com/en-us/visualstudio/code-quality/using-the-cpp-core-guidelines-checkers)
+
+The Microsoft compiler's C++ code analysis contains a set of rules specifically aimed at enforcement of the C++ Core Guidelines. 
+
 # <a name="S-glossary"></a>Glossary
 
 A relatively informal definition of terms used in the guidelines