It doesn't yet get the spec, but it is functional enough to use.
This removed the registration of lmctfy, the code will be removed in a
future PR once raw GetSpec() is complete.
This allows a ContainerHandlerFactory to register a CanHandle() function
which is called to determine whether the factory can handle a particular
container.
This commit disables being able to run cAdvisor without lmctfy. This
should be enabled again with a "no-op" global factory which I would like
to do in a separate PR.
