common: Implement i18n_localegettext.
* common/i18n.c (msg_cache_s, msg_cache_head_s): New. (msgcache): New. (i18n_localegettext): Implement locale dependent lookup.
This is the second and final part of the change to use the gpg
provided locale for Pinentry strings. It does not yet work on
Windows, though.
This commit should resolve
- Debian-bug-id: #788983
- Signed-off-by: Werner Koch <wk@gnupg.org>