Add ability to delete deeply nested attributes in bundled hooks

[ryuken]

Issue #79 asked for the ability to delete deeply nested attributes in a bundled hook like:

hooks.remove("user.password")

I added functionality which checks if the object has the field.
And also a separate function to remove the field

I needed this for myself so I thought I could share and also get a review on my code

[daffl]

Thank you, that makes sense. Could you add a test for this in https://github.com/feathersjs/feathers-hooks/blob/master/test/bundled.test.js#L113?

[daffl]

Awesome! It will go into the next release.