Follow up r2050 with a typo fix.
Follow up r2050 with a typo fix.

* SConstruct: env.append -> env.Append.

x-clone/serf,stoneCC/serf,SirJson/serf,alex1818/serf,lazysoez/serf,soufianeEL/serf,KyleSanderson/serf,yesoce/serf,yesoce/serf,x-clone/serf,SirJson/serf,zhengcq315/serf,google-code-export/serf,google-code-export/serf,KyleSanderson/serf,lazysoez/serf,zhupan/serf,x-clone/serf,SirJson/serf,SirJson/serf,soufianeEL/serf,pengdu/serf,soufianeEL/serf,zhupan/serf,google-code-export/serf,pengdu/serf,pengdu/serf,google-code-export/serf,stoneCC/serf,lazysoez/serf,zhengcq315/serf,stoneCC/serf,zhengcq315/serf,alex1818/serf,lazysoez/serf,yesoce/serf,KyleSanderson/serf,alex1818/serf,zhupan/serf,soufianeEL/serf,alex1818/serf,yesoce/serf,x-clone/serf,pengdu/serf,zhengcq315/serf,KyleSanderson/serf,stoneCC/serf,zhupan/serf