[Developers] Refactoring into "Data World" domain

[Robert Cook]

I just created a new domain for tracking and organizing data import  
projects.  I moved some types from the /common and /freebase domains  
into it and added several others.

http://www.freebase.com/view/domain?id=/dataworld

The types moved are:

/common/data_project_type
/common/data_project
/common/information_source
/common/mass_data_operation

/freebase/type_project
/freebase/type_status
/freebase/type_project_mediator

If you have written code that depends on these types, you will have  
to update it.  It's not generally a good policy to move types like  
this, but as these are support types and we are still in Alpha, we  
went ahead.  In the future, we will put together a more formal  
communication system for such changes.

Robert