Update setenv.sh to support CATALINA_OPTS

[TJM]

Pull Request (PR) description

Updates to setenv.sh support CATALINA_OPTS

* Continuation of PR #140 (@joshbeard)
* Support CATALINA_OPTS either as a string or array of strings
* These changes should support making the setenv.sh with minimal changes
    from 6.0.x (which is EOL soon) to 6.12.x which was just released.
* Change so the "JAVA_OPTS" part only appear for version prior to Confluence 5.x
* Update README for types and to have an example

This Pull Request (PR) fixes the following issues

• Fixes #155
• Continue PR #140 (take over)

[TJM]

sorry, took me a few tries to get the rspec part done. It is still not 100% on the template, but at least I am testing for the catalina_opts parameter

[bastelfreak]

Thanks @TJM !