Removing configuration constructor in favour of fluent API

[ultraq]

In 3.4.0, I introduced a new config option and didn't want to add another constructor option to set it (that made it 3 config options which meant many constructor permutations), so added fluent API methods for each of the options. I'm thinking that the fluent API is way better for these, so I'll look to deprecate the config constructor in a future release, with the plan to remove it at the next major version.