appveyor: optimize build
appveyor: optimize build

GreenCubes/jmonkeyengine,jMonkeyEngine/jmonkeyengine,zzuegg/jmonkeyengine,jMonkeyEngine/jmonkeyengine,atomixnmc/jmonkeyengine,zzuegg/jmonkeyengine,GreenCubes/jmonkeyengine,atomixnmc/jmonkeyengine,atomixnmc/jmonkeyengine,jMonkeyEngine/jmonkeyengine,GreenCubes/jmonkeyengine,atomixnmc/jmonkeyengine,atomixnmc/jmonkeyengine,jMonkeyEngine/jmonkeyengine,zzuegg/jmonkeyengine,zzuegg/jmonkeyengine,atomixnmc/jmonkeyengine,GreenCubes/jmonkeyengine