Log Message:
Update onscripter to 20150102.

Upstream changes (no English changelog):

20150102:
 - fix bug that bgm doesn't stop if game is saved during bgmfadeout
 - change button drawing when mouse is moved out of window
 - fix bug in delay insn that causes extra wait during skip
 - fix bug that settings of kidokumode insn in envdata is overwritten
   by kidokuskip insn at the next startup

20150101:
 - fix bug of bdown insn
 - fix bps insn to ignore undefined lsp
 - fix spbtn insn to ignore undefined lsp
 - fix infinite loop bug during skip by CTRL-key
 - fix segfaults when loading images fails
 - fix bug that skip by CTRL-key doesn't stop when it's released during
   SMPEG is played
 - fix buffer overflow in ScriptHandler.cpp
 - fix bexec insn that can't use number 0
 - allow spaces or tabs before labels in game script
 - update bps insn to handle third arg (mouse bottun event)