Add support for ISO-8859-6 to 16

configure

configure.in

src/backend/utils/mb/Unicode/UCS_to_8859.pl

src/backend/utils/mb/Unicode/iso8859_10_to_utf8.map

src/backend/utils/mb/Unicode/iso8859_13_to_utf8.map

src/backend/utils/mb/Unicode/iso8859_14_to_utf8.map

src/backend/utils/mb/Unicode/iso8859_15_to_utf8.map

src/backend/utils/mb/Unicode/iso8859_16_to_utf8.map

src/backend/utils/mb/Unicode/iso8859_6_to_utf8.map

src/backend/utils/mb/Unicode/iso8859_7_to_utf8.map

src/backend/utils/mb/Unicode/iso8859_8_to_utf8.map

src/backend/utils/mb/Unicode/iso8859_9_to_utf8.map

src/backend/utils/mb/Unicode/utf8_to_iso8859_10.map

src/backend/utils/mb/Unicode/utf8_to_iso8859_13.map

src/backend/utils/mb/Unicode/utf8_to_iso8859_14.map

src/backend/utils/mb/Unicode/utf8_to_iso8859_15.map

src/backend/utils/mb/Unicode/utf8_to_iso8859_16.map

src/backend/utils/mb/Unicode/utf8_to_iso8859_6.map

src/backend/utils/mb/Unicode/utf8_to_iso8859_7.map

src/backend/utils/mb/Unicode/utf8_to_iso8859_8.map