Addressable is inconsistent in escaping uri's with %

Addressable::URI.parse("https://encrypted.google.com/search?abc=%20").normalize.to_s
=> "https://encrypted.google.com/search?abc=%20"

Addressable::URI.parse("https://encrypted.google.com/search?abc=%2B").normalize.to_s
=> "https://encrypted.google.com/search?abc=+"

There is no way to know if normalized uri will have characters escaped or not.

This issue is a result of https://github.com/myronmarston/vcr/issues/86 and bblimke/webmock#134