Document Autoprefixer setting; fixes #899
Document Autoprefixer setting; fixes #899

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bahrul221/bootstrap-sass,thatsus/bs-sass,JasonRivers/bootstrap-sass,zBMNForks/bootstrap-sass,CapeSepias/bootstrap-sass,Wcc723/capstrap-open,sonipalak/demo,kyled09/splashPage,ruiii/bootstrap-sass,sonipalak/demo,JasonRivers/bootstrap-sass,Wcc723/capstrap-open,bahrul221/bootstrap-sass,bahrul221/bootstrap-sass,smartexpose/twbs-bootstrap-sass,CapeSepias/bootstrap-sass,thatsus/bs-sass,Wcc723/capstrap-open,kyled09/splashPage,JasonRivers/bootstrap-sass,thatsus/bs-sass,smartexpose/twbs-bootstrap-sass,twbs/bootstrap-sass,sonipalak/demo,smartexpose/twbs-bootstrap-sass,twbs/bootstrap-sass,thatsus/bs-sass,kyled09/splashPage,bahrul221/bootstrap-sass,CapeSepias/bootstrap-sass,zBMNForks/bootstrap-sass,JasonRivers/bootstrap-sass,ruiii/bootstrap-sass,ruiii/bootstrap-sass,ruiii/bootstrap-sass,Wcc723/capstrap-open,smartexpose/twbs-bootstrap-sass,CapeSepias/bootstrap-sass,twbs/bootstrap-sass,zBMNForks/bootstrap-sass,zBMNForks/bootstrap-sass,twbs/bootstrap-sass,sonipalak/demo,kyled09/splashPage