The `nodeify` utility is no longer needed for the background API.
Instead each method is assumed to be either synchronous or Promise-
returning.
The error handling was updated to at least log the error in the case
where a method fall fails after the connection is broken.
The `assert` module has two modes: "Legacy" and "strict". When using
strict mode, the "strict" version of each assertion method is implied.
Whereas in legacy mode, by default it will use the deprecated, "loose"
version of each assertion.
We now use strict mode everywhere. A few tests required updates where
they were asserting the wrong thing, and it was passing beforehand due
to the loose matching.
