install nw-gyp in 32 bit environment if NODE_WEBKIT is not empty
install nw-gyp in 32 bit environment if NODE_WEBKIT is not empty

Note: `make clean` happens after `npm install nw-gyp -g` because we intend to use `nw-gyp` later to rebuild the existing build of node-sqlite3.
briangreenery/node-sqlite3,march1993/node-sqlite3,strongloop-forks/node-sqlite3,tomhughes/node-sqlite3,ashikcse20/node-sqlite3,t3mulligan/node-sqlite3,dragonfly-science/node-sqlite3,damonpetta/node-sqlite3,FeodorFitsner/node-sqlite3,FeodorFitsner/node-sqlite3,jBarz/node-sqlite3,damonpetta/node-sqlite3,FeodorFitsner/node-sqlite3,kevinsawicki/node-sqlite3,t3mulligan/node-sqlite3,strongloop-forks/node-sqlite3,mapbox/node-sqlite3,mapbox/node-sqlite3,tsufeki/node-sqlite3,kkoopa/node-sqlite3,liubiggun/node-sqlite3,kenr/node-sqlite3,kevinsawicki/node-sqlite3,dragonfly-science/node-sqlite3,liubiggun/node-sqlite3,t3mulligan/node-sqlite3,bengotow/node-sqlite3,javiergarmon/node-sqlite3,jBarz/node-sqlite3,ashikcse20/node-sqlite3,kkoopa/node-sqlite3,dragonfly-science/node-sqlite3,tsufeki/node-sqlite3,mapbox/node-sqlite3,tsufeki/node-sqlite3,kkoopa/node-sqlite3,Finkes/node-sqlite3,alejandronunez/sqlitenw,briangreenery/node-sqlite3,jBarz/node-sqlite3,jBarz/node-sqlite3,jBarz/node-sqlite3,liubiggun/node-sqlite3,kenr/node-sqlite3,alejandronunez/sqlitenw,jBarz/node-sqlite3,march1993/node-sqlite3,kevinsawicki/node-sqlite3,javiergarmon/node-sqlite3,bengotow/node-sqlite3,kenr/node-sqlite3,liubiggun/node-sqlite3,damonpetta/node-sqlite3,alejandronunez/sqlitenw,dragonfly-science/node-sqlite3,Finkes/node-sqlite3,mapbox/node-sqlite3,tsufeki/node-sqlite3,strongloop-forks/node-sqlite3,kevinsawicki/node-sqlite3,javiergarmon/node-sqlite3,FeodorFitsner/node-sqlite3,bengotow/node-sqlite3,tomhughes/node-sqlite3,tomhughes/node-sqlite3,FeodorFitsner/node-sqlite3,alejandronunez/sqlitenw,javiergarmon/node-sqlite3,bengotow/node-sqlite3,march1993/node-sqlite3,bengotow/node-sqlite3,kkoopa/node-sqlite3,briangreenery/node-sqlite3,Finkes/node-sqlite3,liubiggun/node-sqlite3,javiergarmon/node-sqlite3,dragonfly-science/node-sqlite3,ashikcse20/node-sqlite3,kkoopa/node-sqlite3,dragonfly-science/node-sqlite3,damonpetta/node-sqlite3,kenr/node-sqlite3,damonpetta/node-sqlite3,tomhughes/node-sqlite3,Finkes/node-sqlite3,alejandronunez/sqlitenw,t3mulligan/node-sqlite3,kevinsawicki/node-sqlite3,briangreenery/node-sqlite3,strongloop-forks/node-sqlite3,t3mulligan/node-sqlite3,march1993/node-sqlite3,tomhughes/node-sqlite3,briangreenery/node-sqlite3,tomhughes/node-sqlite3,bengotow/node-sqlite3,Finkes/node-sqlite3,mapbox/node-sqlite3,ashikcse20/node-sqlite3,Finkes/node-sqlite3,damonpetta/node-sqlite3,kkoopa/node-sqlite3,tsufeki/node-sqlite3,briangreenery/node-sqlite3,ashikcse20/node-sqlite3,march1993/node-sqlite3,liubiggun/node-sqlite3,FeodorFitsner/node-sqlite3,mapbox/node-sqlite3,kenr/node-sqlite3,march1993/node-sqlite3,ashikcse20/node-sqlite3,t3mulligan/node-sqlite3,strongloop-forks/node-sqlite3,strongloop-forks/node-sqlite3,javiergarmon/node-sqlite3,tsufeki/node-sqlite3,alejandronunez/sqlitenw,kevinsawicki/node-sqlite3,kenr/node-sqlite3