[PATCH] automated demangling styles list.

[DJ Delorie]

> 	* demangle.h (demangling_styles): Renumbered.
> 	(demangler_engine): Restructured.

Neither of these are backward compatible.  For demangling_styles,
please preseve the previous values for previous enumerations.  For
demangler_engine, please add new fields only at the end so that
existing fields remain at the same offset (although, since it's an
*array* of structs, even extending breaks old binaries).