Enable the simple raw driver.

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.
Merge pull request #99 from vmarmol/raw

Enable the simple raw driver.
Features:
Added Network Stats to Container Info. It still not exposed via the HTTP UI.
Bug fixes:
1. Modified docker handler to use libcontainer.GetStats instead of quering the fs package.
2. cAdvisor will not stall if any of its core operations fail.
3. cAdvisor will safely ignore any inactive or leaked docker containers. When containers are leaked cgroup state exists but docker is not aware of them.
Adding utils package
Fix raw cgroups handler.
Fixed bugs introduced in previous patches.
Addressed comments. Another series of bug fixes.
Modified the docker driver and lmctfy driver to skip containers they cannot handle.
Remove Unsupported special error code from the containers factory.
Avoid listing self while listing docker subcontainers.
Revert changes to container manager Start() interface.