Use common initialization for database adapters

[daffl]

To have all adapters work similar, we may want to change having to use new to instantiate a new service instance like:

// Connect to the db, create and register a Feathers service.
app.use('todos', new nedbService('todos'));

to just a function call:

// Connect to the db, create and register a Feathers service.
app.use('todos', nedb('todos'));

[daffl]

Oh nevermind you're using Uberproto right? I don't think the new is necessary at all. Mind if I update it in the docs?

[marshallswain]

Make it happen. Sounds good.

[daffl]

Closed via e19c8ff10ae69179f61eb7ce84d2a2969e700ca3