make clearer that language:node_js should be removed if running multi-os
make clearer that language:node_js should be removed if running multi-os

hybridgroup/node-pre-gyp,fengmk2/node-pre-gyp,synthetos/node-pre-gyp,etiktin/node-pre-gyp,etiktin/node-pre-gyp,fengmk2/node-pre-gyp,mojodna/node-pre-gyp,hybridgroup/node-pre-gyp,mapbox/node-pre-gyp,fengmk2/node-pre-gyp,etiktin/node-pre-gyp,mojodna/node-pre-gyp,etiktin/node-pre-gyp,hybridgroup/node-pre-gyp,fengmk2/node-pre-gyp,synthetos/node-pre-gyp,fengmk2/node-pre-gyp,mapbox/node-pre-gyp,mapbox/node-pre-gyp,mojodna/node-pre-gyp,synthetos/node-pre-gyp,mojodna/node-pre-gyp,etiktin/node-pre-gyp,mapbox/node-pre-gyp,mojodna/node-pre-gyp,synthetos/node-pre-gyp,hybridgroup/node-pre-gyp,mapbox/node-pre-gyp,synthetos/node-pre-gyp