Fixed bug with webkit version validation
Fixed bug with webkit version validation

Validation failed with older versions of node webkit prior to the renaming from node-webkit to nwjs.

daemonchen/generator-node-webkit,j-hernandez/generator-node-webkit,j-hernandez/generator-node-webkit,teoria/generator-node-webkit,teoria/generator-node-webkit,ace68723/generator-node-webkit,ace68723/generator-node-webkit,napalmdev/generator-node-webkit,Dica-Developer/generator-node-webkit,teoria/generator-node-webkit,j-hernandez/generator-node-webkit,napalmdev/generator-node-webkit,daemonchen/generator-node-webkit,daemonchen/generator-node-webkit,ace68723/generator-node-webkit,napalmdev/generator-node-webkit,Dica-Developer/generator-node-webkit,Dica-Developer/generator-node-webkit