Added Nested/Recursive BOB Directories

I made these changes for myself a while back I figured they might be useful to the community

* Added loading of `CustomObject`s from all subfolders of parent BOB
directory
     * Loaded `CustomObject`s are not enabled until after all recursive calls
have been made

Global object loading looks something like this...
![2013-07-16_1521-a](https://f.cloud.github.com/assets/1635159/807378/65dd6528-ee4d-11e2-8d27-a1c014681a7b.png)

Individual World Loading looks something like this...(Notice the Number error in between: That is another change I made to help me find errors in files... If you want me to create a pull request for that too let me know ;)
![2013-07-16_1521-b](https://f.cloud.github.com/assets/1635159/807380/685211e6-ee4d-11e2-9aff-095f635d8e9e.png)