Build Gulp task dos not include vendor JS

[kokujin]

The "build" task needs that the application should be hardcoded in production mode to trigger the building of vendor JS files. Setting the env manually does not work.

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I think there should be a task called build_production that would build all assets ready to be deplyoed to a production server because in most cases, the developer uses a deployment tool to transfer the build to a remote server, his/her development machine is never in production mode.

I really appreciate your work, it really is a lot to implement. This is one of the best scaffolding tool/generator I have tested so far. 
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[arvindr21]

@kokujin Thanks for your comments! I will add the production build task over the weekend.