support for cp949

Apart from euc-kr, there are also cp949 for Korean encoding. It's default encoding for Korean Windows OS thus widely accepted in Korea.

cp949 is superset for euc-kr, so there are additional characters especially in 0x8140-0xa0ff.
(see http://www.i18nl10n.com/korean/cp949l.html#hangul2)

Strictly 0x8140-0xa0ff range is not euc-kr encoding, but this will temporarily support cp949 encoding in iTerm.