Updated Bulgarian translation

Hi guys,

I am Alexander Shopov - the committer of the Bulgarian Gnome translation
team.

I am sending the updated translation for Abiword.
The name of the translator is Yasen Pramatarov <yasen@lindeas.com>
He is the same translator as before - he just changed his e-mail.

I am sending the translations for both the ABI-2-4-0-STABLE and HEAD
branches.

Please commit them.

The translations are now in *UTF-8*, not in CP1251 encoding as they
previously were.

Kind regards:
al_shopov