Iconv cleanup, stage 1a: remove `g' prefix from binaries, headers, libraries and
manpages installed by libiconv (aka GNU iconv) and add similar `b'-prefixes
into components installed by iconv (aka BSD iconv). The reason why we do this
is because unfortunately BSD iconv become abadonware (author doesn't maintain
it anymore), while number of ports that need functional iconv library grows
very fast, thus creating significant overhead due to patches needed to make
ports working with prefixed GNU iconv. For compatibility reasons create
symlinks in GNU iconv, so that all ports that expect GNU iconv to have `g'
prefix should work unmodified until all those `g'-hacks are wiped out.
Prompted by: ache
Reviewed by (in principle): freebsd-ports, freebsd-gnome