Translated 'WebRTC data channels' into Korean
Review & suggests: modified links to korean rocks' articles, tweaked awkwards and so on.
Merge pull request #2 from cwdoh/ko.review.sbnet21.webrtc.datachannel

리뷰: WebRTC DataChannel
Polish the Korean translation of 'datachannels'
Merge pull request #966 from sbnet21/webrtc

Translate 'datachannels' into Korean