be_BY, be_BY@latin: Add alternative month names (bug 10871).
This patch also fixes spelling of lang_name in be_BY@latin, as reported
by Ihar Hrachyshka.
[BZ #10871]
* localedata/locales/be_BY (mon): Rename to...
(alt_mon): This, then synchronize with CLDR (nominative case).
(abmon): Rename to...
(ab_alt_mon): This, then synchronize with CLDR (nominative case).
(mon): Import from CLDR (genitive case).
(abmon): Likewise.
* localedata/locales/be_BY@latin (mon): Rename to...
(alt_mon): This.
(mon): Add, proper genitive forms provided by Viktar Siarheichyk.
* localedata/locales/be_BY@latin (lang_name): Reworded to
"biełaruskaja mova".