[Python-3000] Draft PEP: Using UTF-8 as the default source encoding

["Martin v. Löwis"]

> +1 in general. Do you want to add a sentence or two about the infamous
> UTF-8 "BOM"?

Can do. Strictly speaking, it's covered by PEP 263 already, which makes
presence of the BOM equivalent to an encoding declaration.

Regards,
Martin