Update ruby-patronto 0.4.20.

* fix base url concatenation

* Adds instantiation settings via block or hash.
  Fixes .downcase being called on symbols.

  Cleaned up

  Cleans up hash setter. Adds block support

  Adds tests for hash and block instantiation

  Undoes string fix for patron/request.rb to keep with scope.

* Handle two failing specs

  One is failing due to no OS support for SSLv2. This is reasonable,
  so I just removed SSLv2 from the list of SSL versions to test. This
  doesn't change the meaning of the test at all.

  I could not find the root cause of the other spec failure, though
  I suspect it is a setup problem. I have disabled the spec for now
  and will revisit it later on.

* Add doc comment
* Add a way to get the Request object

* Revert request action to be a symbol, but still allow upcase and
  downcase strings.

(taca)