Ensure jenkins jobs are updated on every run

Currently, the -data repo jenkin jobs files are manually copied.
If files are deleted in the -data repo, then extra files are left
around in the jenkins config folder, causing conflicts.
As well, if there are only changes to these files, then puppet won't
reload the jenkins jobs into jenkins, requiring the user to do so
manually.

Instead, simply delete all the files, and copy them over again.
Puppet will install the files it manages and all jobs will get reloaded
into jenkins.