Fix changing tool mode through arrow keys. 
Fix changing tool mode through arrow keys. 
ycaihua/skim-app,WoLpH/skim,WoLpH/skim,WoLpH/skim,WoLpH/skim,WoLpH/skim,ycaihua/skim-app,ycaihua/skim-app,ycaihua/skim-app,ycaihua/skim-app