be-tarask language subtag registration form

[Frank Ellermann]

zedlik wrote:

> in Internet Taraskievica is used much oftener than Narkamauka

If that's the case it could be better to register both variants,
maybe using "1933" or "1959" for the official orthography.

The application I've in mind are spell checkers, they could ask
the user or pick a user defined default for "be" texts without
variant, and otherwise they'd use "tarask" vs. "1993" or "1959".

Frank