Log Message:
Update ruby-net-ssh to 2.9.2.

=== 2.9.2-rc3

* Remove advertised algorithms that were not working \ 
(curve25519-sha256@libssh.org) [mfazekas]

=== 2.9.2-rc2

* number_of_password_prompts is now accepted as ssh option, by setting it 0 \ 
net-ssh will not ask for password for password auth as with previous versions \ 
[mfazekas]

=== 2.9.2-rc1

* Documentation fixes and refactoring to keepalive [detiber, mfazekas]

=== 2.9.2-beta

* Remove advertised algorithms that were not working (ssh-rsa-cert-* *ed25519 \ 
acm*-gcm@openssh.com) [mfazekas]
* Unkown algorithms now ignored instead of failed [mfazekas]
* Asks for password with password auth (up to number_of_password_prompts) [mfazekas]
* Removed warnings [amatsuda]

=== 2.9.1 / 13 May 2014

* Fix for unknown response from agent on Windows with 64-bit PuTTY [chrahunt]
* Support negative patterns in host lookup from the SSH config file [nirvdrum]

=== 2.9.0 / 30 Apr 2014

* New ciphers [chr4]
  * Added host keys: ssh-rsa-cert-v01@openssh.com ssh-rsa-cert-v00@openssh.com \ 
ssh-ed25519-cert-v01@openssh.com ssh-ed25519
  * Added HMACs: hmac-sha2-512-etm@openssh.com hmac-sha2-256-etm@openssh.com \ 
umac-128-etm@openssh.com
  * Added Kex: aes256-gcm@openssh.com aes128-gcm@openssh.com \ 
curve25519-sha256@libssh.org
  * Added private key support for id_ed25519
* IdentiesOnly will not disable ssh_agent - fixes #148 and new fix for #137 \ 
[mfazekas]
* Ignore errors during ssh agent negotiation [simonswine, jasiek]
* Added an optional "options" argument to test socket open method \ 
[jefmathiot]
* Added gem signing (again) with new cert [delano]

=== 2.8.1 / 19 Feb 2014

* Correct location of global known_hosts files [mfischer-zd]
* Fix for password authentication [blackpond, zachlipton, delano]