The current way is broken as it chokes while unescaping characters that are not allowed non-escaped in the userinfo URI component, such as "@" if the username is an email address.
Being a nice Ruby citizen means not mutating the @proxy_uri which is an object that might have came from the user.
@proxy_uri
which is an object that might have came from the user.References #54 #56. Fixes #48
/cc @juhakaja @tumf