RequireLibrary is not a service--it is a mini-framework for registering service libraries with Needle so that they can be imported into other projects with a minimum of headache.

Currently, Needle supports @Container#require@ as the library import mechanism. This requires you to specify both the file containing the service registration method, as well as the Module that contains the method.

RequireLibrary takes some of the duplication out of the process by allowing application developers to register a callback hook with Needle, which will be invoked when the new @Container#require_library@ method is invoked.
