Fixed korean locale words.

Two fixes.

1. `현재` -> `지금` for _now_.

  I think it is better. `현재` means "current" and `지금` menas "right now".

2. `초` -> `몇초` for _seconds_.

  (explain: "초": "second", "전": "ago", "몇": "few")
  If we translate "seconds ago" to korean, it should be "몇초 전" for making sense.