20210424a

• Fix bug in Function.IsTrivial.
• Fix Parser to handle nested brace initialization.
• Fix file count in "n files should be parsed to avoid spurious results."
• Change some warnings to be logged on a C++ item rather than only by position.
• Refactor functions involving LineType.
• Log ClassCouldBeNamespace on a class that is never constructed and that only has public static members.
• Log CtorCouldBeDeleted on a class that only has static members if some of them are not public.
• Log CopyCtorNotDeleted and CopyOperNotDeleted on base classes whose leaf classes are singletons and on singletons without such a base class.
• Improve >fix for special member functions (warning numbers 57, 58, 59, 60, 64, 66, 68, 69, 70, 71, 128, 129, 134, 135, 136).
• Apply >fix for special member functions to all files after removing all defaulted and deleted functions.