Add default script on package.json

[pragmaticivan]

Here: https://github.com/wedeploy/generator-electric/blob/master/generators/app/templates/package.json

maybe: npm run build => gulp build npm run deploy => gulp deploy npm run server => gulp server npm run watch => gulp watch

[zenorocha]

https://github.com/electricjs/generator-electric/commit/87ca749314979f4f033dc8fbf0f26a965284a97d