SSL params bug fixes and improvements

Pull request #6 broke SSL connections:

* get_ssl while connecting should receive the host and port we are
 trying to connect to, since current_host_and_port may not be set yet.

* local variable ssl redefines ssl module, shadowing it

* SSL connection test fails, however there's an except block catching
  all errors and test pass even if it shouldn't.

* Expose set_ssl/get_ssl methods to connection objects
fix conflicts after merging Rafael's patch
minor improvement to test coverage
update changelog