Hooks shouldn't be arrow functions

Hooks should not return arrow functions because the context (this) is the surrounding context, not the service (which is being set on normal functions).

[daffl]

It’d be more of a consistency thing (also, plain functions might be a little faster since they don’t need to be explicitly bound to another context).

Maybe we should add a hook.service? People were confused about what this is in a hook before. It’d be pretty easy to add.

[eddyystop]

daffl has added hook.service and hook.path to feathers-hooks.