Updated com.jcraft.jsch to 0.1.51
Updated com.jcraft.jsch to 0.1.51

The reason for this is that communication with Gerrit might be lost under
high-pressure load situations when using recent Java7 releases.

The issue that occurs is the "verify:false" problem outlined in the
changelog for 0.1.51:
http://www.jcraft.com/jsch/ChangeLog

The actual error that will appear runs like this:
-----------------------------------------------------
Feb 02, 2015 2:42:20 PM com.sonymobile.tools.gerrit.gerritevents.workers.cmd.AbstractSendCommandJob sendCommand
SEVERE: Could not run command gerrit approve 60123,1 --message 'Build Successful
[...]
https://<URL>/b/job/<JOB>/2502/ : SUCCESS' --verified 1 --code-review 0
java.io.IOException: Error during sending command
[...]
Caused by: com.sonymobile.tools.gerrit.gerritevents.ssh.SshException: com.jcraft.jsch.JSchException: verify: false
-----------------------------------------------------

Updating to 0.1.51 fixes this issue.

rinrinne/gerrit-events,svanoort/gerrit-events,scoheb/gerrit-events,dpursehouse/gerrit-events,sonyxperiadev/gerrit-events