Use "previous" AppVeyor env as temp workaround for nodejs/node-gyp#952
Use "previous" AppVeyor env as temp workaround for nodejs/node-gyp#952

lovell/sharp,brandonaaron/sharp,brandonaaron/sharp,pporada-gl/sharp,mdimitrov/sharp,digital-flowers/sharp-win32,mhirsch/sharp,digital-flowers/sharp-win32,pporada-gl/sharp,mdimitrov/sharp,brandonaaron/sharp,lovell/sharp,mhirsch/sharp,pporada-gl/sharp,mdimitrov/sharp,cmtt/sharp,pporada-gl/sharp,digital-flowers/sharp-win32,brandonaaron/sharp,digital-flowers/sharp-win32,brandonaaron/sharp,lovell/sharp,digital-flowers/sharp-win32,mhirsch/sharp,lovell/sharp,lovell/sharp,digital-flowers/sharp-win32,cmtt/sharp,cmtt/sharp,pporada-gl/sharp,digital-flowers/sharp-win32,mdimitrov/sharp,lovell/sharp,mdimitrov/sharp,cmtt/sharp,mhirsch/sharp