Pull request:

https://github.com/jenkinsci/jira-issue-updater-plugin/pull/1

This PR added the possibility to update fixed versions of jira issues:

• appends the versions to / overwrites the original fixed versions
• environment/build variable substitution supported (as the plugin already did)
• non-applicable versions (since versions are project specific) are ignored, error messages are logged.

Reviews and comments are greatly appreciated.