Log Message:
Update p5-Net-OpenSSH to 0.52.

Changes from previous:
0.52  May 9, 2011
        - release as stable
        - skip bad passwd test when IO::Pty is not available

0.51_12  May 2, 2011
        - require version 2 of the SSH protocol (bug report by Jo
          Rhett)
        - remove harmless "my $foo = ... if ..." bug

0.51_11  Apr 24, 2011
        - encoding handling in sftp method was broken (bug report and
          solution by Todd Rinaldo)
        - sftp method was broken (regression)
        - better support for sharing SSH connections with children
        - more tests
        - add sample for usage with Net::Telnet
        - bad sample in documentation corrected

0.51_10  Mar 29, 2011
        - error status was not reset between calls (regression)
        - remove internal line numbers from error messages
        - encoding errors were not propageted in pipe_in and pipe_out
          methods
        - minor debuging cleanup
        - better messages on bad encoding errors

0.51_09  Mar 29, 2011
        - add support for passphrase protected keys
        - add support for passing the private key path as an explicit
          constructor option
        - bug solved on password handling
        - bug solved in _fileno_dup_over
        - remove redundant _check_master_and_clear_error
        - more tests
        - some doc improvements

0.51_08  Mar 28, 2011
        - pipe_in and pipe_out were not correctly setting error status
          on failure
	- support argument_encoding in pipe_in and pipe_out
        - document how to set StrictHostKeyChecking=no
        - replace @error_prefix arguments by a localized stack
	- use _load_module for Encode loading
	- remove no-encoding hack on _master_ctl

0.51_07  Mar 22, 2011
        - add encoding support
        - undef $SIG{CHLD} inside blocking methods

0.51_06  Mar 16, 2011
        - make hostname argument to constructor optional when
          external_master is set
        - better error handling in constructor
        - s/reuse_master/external_master/. I never were happy with the
          old option name.
        - some minor doc corrections

0.51_05  Mar 15, 2011
        - implement reuse_master feature
        - do not propagate extra arguments from wait_for_master to
          _wait_for_master
        - accept ssh_opts in make_remote_command

0.51_04  Mar 10, 2011
        - solve "Not enough arguments for grep" bug (reported by Tom
          Wittbrodt)
        - some documentation improvements

0.51_03  Mar 9, 2011
        - error message corrected
        - troubleshooting guide improved
        - add pointer to OpenSSH Wikibook
        - add autosudo.pl sample
        - implement stdintout_dpipe_is_parent feature

0.51_02  Feb 10, 2011
        - add support for test method
        - add support for dpipe feature
        - simplify _wait_for_master code
        - remove spurious warnings generated when control command
          failed to run (bug report by jaiieq from Perlmonks)
	- timeout at object level where being ignored by _waitpid
        - document how to run detached remote processes

0.51_01  Feb 1, 2011
        - add support for kill_ssh_on_timeout feature and better
          timeout handling
        - set ssh option ServerAliveInterval
        - system could return -1 on error instead of false
        - add change_password.pl sample
	- some tests were failing when using csh as the remote shell
          (bug report by Scott Davis)