Name mangling

[Daveed Vandevoorde]

Thanks for your remarks Christophe.  I have integrated them in the
"document" (big word for a little file right now ;-).

I also added an item about identifier extensions.  I know that several
vendors have a mode that accepts '$' as part of a C/C++ identifier.  Are
there any other such extended characters that should go through unencoded
(i.e., we could encode them along the strategy we'll select for universal
character names, but I doubt that's what we want for '$' for example.)

	Daveed