Implement multiple function signature styles for JavaScript services

[Marak]

In order to support all Function as a Service providers, we should allow our JavaScript services to accept multiple function signatures.

This will have to be a manual setting on Hook creation or update.

Styles could include:

function (hook) {} )
function (hook, cb) {} )
function (req, res, next) {} )

Will continue to update as more information comes in.

Currently a Medium-Low Priority.