Set Content-Type on static files.
Set Content-Type on static files.

Fixes #763

CrazyJvm/cadvisor,megamsys/cadvisor,erSitzt/cadvisor,dchen1107/cadvisor,linux-on-ibm-z/cadvisor,CrazyJvm/cadvisor,ncdc/cadvisor,c-st/cadvisor,linux-on-ibm-z/cadvisor,linux-on-ibm-z/cadvisor,yolkov/cadvisor,hw-qiaolei/cadvisor,aivarasko/cadvisor,bowlofstew/cadvisor,rajthilakmca/cadvisor,vegasbrianc/cadvisor,jhjeong-kr/cadvisor,takecy/cadvisor,c-st/cadvisor,feiskyer/cadvisor,ainsleyc/cadvisor,afein/cadvisor,bowlofstew/cadvisor,derekwaynecarr/cadvisor,dchen1107/cadvisor,atyenoria/cadvisor,Snorch/cadvisor,derekwaynecarr/cadvisor,bowlofstew/cadvisor,timstclair/cadvisor,shilpamayanna/cadvisor,IFTTT/cadvisor,atyenoria/cadvisor,aivarasko/cadvisor,jhjeong-kr/cadvisor,ChengTiesheng/cadvisor,yolkov/cadvisor,guoshimin/cadvisor,aivarasko/cadvisor,c-st/cadvisor,morpheyesh/cadvisor,wulonghui/cadvisor,jhjeong-kr/cadvisor,jimmidyson/cadvisor,ainsleyc/cadvisor,Snorch/cadvisor,mangalaman93/cadvisor,carmark/cadvisor,vegasbrianc/cadvisor,derekwaynecarr/cadvisor,anarcher/cadvisor,jzaefferer/cadvisor,bing6/cadvisor,ncdc/cadvisor,bing6/cadvisor,f0/cadvisor,erSitzt/cadvisor,ChengTiesheng/cadvisor,jimmidyson/cadvisor,ChengTiesheng/cadvisor,rajthilakmca/cadvisor,BrickXu/cadvisor,jhjeong-kr/cadvisor,Snorch/cadvisor,f0/cadvisor,feiskyer/cadvisor,BrickXu/cadvisor,timstclair/cadvisor,wulonghui/cadvisor,megamsys/cadvisor,BrickXu/cadvisor,dchen1107/cadvisor,morpheyesh/cadvisor,hzy001/cadvisor,jimonreal/cadvisor,anarcher/cadvisor,vishh/cadvisor,IFTTT/cadvisor,BrickXu/cadvisor,rajthilakmca/cadvisor,datawisesystems/cadvisor,hacpai/cadvisor,erSitzt/cadvisor,jimonreal/cadvisor,yifan-gu/cadvisor,takecy/cadvisor,IFTTT/cadvisor,afein/cadvisor,vishh/cadvisor,hacpai/cadvisor,yifan-gu/cadvisor,derwolfe/cadvisor,kmicheal/cadvisor,pwittrock/cadvisor,whosthatknocking/cadvisor,guoshimin/cadvisor,derwolfe/cadvisor,dchen1107/cadvisor,hacpai/cadvisor,anarcher/cadvisor,derekwaynecarr/cadvisor,whosthatknocking/cadvisor,kmicheal/cadvisor,mangalaman93/cadvisor,derwolfe/cadvisor,ainsleyc/cadvisor,hw-qiaolei/cadvisor,hzy001/cadvisor,mangalaman93/cadvisor,mr-justin/cadvisor,ncdc/cadvisor,ncdc/cadvisor,f0/cadvisor,hzy001/cadvisor,f0/cadvisor,jzaefferer/cadvisor,jzaefferer/cadvisor,IFTTT/cadvisor,derekwaynecarr/cadvisor,dalanlan/cadvisor,dalanlan/cadvisor,mr-justin/cadvisor,yolkov/cadvisor,whosthatknocking/cadvisor,jmaitrehenry/cadvisor,yifan-gu/cadvisor,pwittrock/cadvisor,ainsleyc/cadvisor,normanjoyner/cadvisor,guoshimin/cadvisor,datawisesystems/cadvisor,jhjeong-kr/cadvisor,mr-justin/cadvisor,IFTTT/cadvisor,hw-qiaolei/cadvisor,CrazyJvm/cadvisor,jmaitrehenry/cadvisor,erSitzt/cadvisor,carmark/cadvisor,feiskyer/cadvisor,difro/cadvisor,shilpamayanna/cadvisor,ncdc/cadvisor,f0/cadvisor,jimonreal/cadvisor,BrickXu/cadvisor,dchen1107/cadvisor,jmaitrehenry/cadvisor,pwittrock/cadvisor,erSitzt/cadvisor,wulonghui/cadvisor,kmicheal/cadvisor,takecy/cadvisor,difro/cadvisor,difro/cadvisor,vishh/cadvisor,bing6/cadvisor,dalanlan/cadvisor,jimmidyson/cadvisor,atyenoria/cadvisor,timstclair/cadvisor,vegasbrianc/cadvisor,normanjoyner/cadvisor