Update jenkins-slave.RedHat init.d script work bash < 4.0

[andrewegel]

(First pull request, please be gentle)

Related to issue #225

This change makes the init script work on CentOS-5.x - or really any host using bash less than version 4.0. This is the original error I was receiving:

# service jenkins-slave start
Starting Jenkins Slave...
-bash: -c: line 0: syntax error near unexpected token `>'
-bash: -c: line 0: `/usr/bin/java  -jar /home/jenkins-slave/swarm-client-1.22-jar-with-dependencies.jar -mode normal -executors 1  -name <redacted> -master <redacted> -labels '<redacted>' -fsroot '/home/jenkins-slave'  &>> /var/log/jenkins-slave/jenkins-slave.log &'

This change is more portable than the original command line. So even if this project doesn't want to support CentOS-5.x, this change still guards against shell "gotchas" like this.

[jenkinsadmin]

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[jhoblitt]

Does >> $JENKINS_SLAVE_LOG 2>&1 work with your version of bash? That would be a bit DRYer.

[andrewegel]

I like your way better - It does indeed work in bash < 4.0 - Pull request modified

[andrewegel]

@jhoblitt Is this diff to your liking? I would really like to get this change in so we may use this puppet class stock in our infrastructure where I work, and this is the only change needed to get Jenkins "swarm" slaves functioning on CentOS-5.x in our infrastructure.

[andrewegel]

@jhoblitt & @rtyler Any reason this change hasn't been merged? We (team I work on) would like to use this puppet module, and this change is preventing us from getting this module working on CentOS 5.8 slaves. This seems like a pretty minor change to get it working.

[jhoblitt]

The PR passed the acceptance tests on the centos-65-x64 nodeset -- I'm going to go ahead and merge it.

[andrewegel]

Thanks @jhoblitt

[jhoblitt]

@andrew-sumner No, thank you both for work on fixing this and your patience in getting it merged.