Work on jboss refactoring

Hi @us3r777,

This pull requests is a review of the JBOSS refactoring you've started here: https://github.com/rapid7/metasploit-framework/pull/3540

I had some concerns about the current refactoring, so I'm trying to make a proposal in this pull request. It includes:

* Split the BeanShell namespace
* Refactor the BeanShell generation methods
* Refactor some big methods

Feel free to review / test / comment, you can land this pull request into your repository, and take what you like for your pull request. Then we can continue going ahead with https://github.com/rapid7/metasploit-framework/pull/3540

thanks!