Configurable 'globalization' of _ and async

[mikermcneil]

I'd love to make _ and async disableable (see https://github.com/balderdashy/sails/blob/master/lib/sails.js#L16) with the same global config. It won't be hard, just a matter of going through all the files and making sure we're requiring _ and async.

[particlebanana]

Awesome this can be closed!

[mikermcneil]

Thanks @particlebanana