#2 make plugins rebuildable

[Lee Harr]

Originally reported on Google Code with ID 3 ``` What steps will reproduce the problem? 1. Rebuild a module
2. Any classes loaded from plugins become unavailable
3. In order to see changes in plugins, the server must be restarted

What is the expected output?
Make changes in plugins !rebuild .module plugin gets loaded to. or !rebuild plugins Changes are available

What do you see instead?
@clone Dog # Dog class is in a plugin module dog created.
!rebuild mobs
@clone Dog
No Dog to clone.