maint: spelling fixes, including author names

maint: spelling fixes, including author names

Most of this just affects commentary and documentations.  The only
significant behavior change is translating author names via
proper_name_lite rather than proper_name_utf8, or not translating
them at all.  proper_name_lite is good enough for coreutils and
avoids the bloat that had coreutils not using Gnulib proper_name.
* bootstrap.conf (gnulib_modules): Use propername-lite instead
of propername.
(XGETTEXT_OPTIONS): Look for proper_name_lite instead of for
proper_name_utf8.
* cfg.mk (local-checks-to-skip): Remove
sc_proper_name_utf8_requires_ICONV, since we no longer use
proper_name_utf8.
(old_NEWS_hash): Update.
(sc_check-I18N-AUTHORS): Remove; no longer needed.