isearch-hangul-switch-symbol-ksc, isearch-hangul-switch-hanja):
New functions.
(korean-key-bindings): Renamed from exit-korean-environment-data.
Initialized apropriately.
(setup-korean-environment): Setup key bindings according to
korean-key-bindings.
(exit-korean-environment): Revert key bindings only if the current
key bindings is the same as what set by setup-korean-environment.