upgrade sbt to 0.12.4
cs "česky, čeština" translation #3103. Author: Mhyrtuu.
hi "हिन्दी, हिंदी" translation #3104. Author: Phani. Longer sentences or clearer sentences would have been easy to translate
sk "slovenčina" translation #3105. Author: Anonymous.
es "español, castellano" translation #3106. Author: Anonymous.