Log Message:
Update ruby-addressable to 2.4.0.

# Addressable 2.4.0
- support for 1.8.x dropped
- double quotes in a host now raises an error
- newlines in host will no longer get unescaped during normalization
- stricter handling of bogus scheme values
- stricter handling of encoded port values
- calling `require 'addressable'` will now load both the URI and Template files
- assigning to the `hostname` component with an `IPAddr` object is now supported
- assigning to the `origin` component is now supported
- fixed minor bug where an exception would be thrown for a missing ACE suffix
- better partial expansion of URI templates