Add an IPAllocator type
Initial support of propogating the termination reasons and image failure
to apiserver. Deprecated docker.Container from API completely.

Conflicts:
	pkg/api/types.go
	pkg/kubelet/kubelet.go
Clean unittests
Fix rebase issues.
Fix e2e tests.
Addressed comments.
Merge pull request #1594 from thockin/ipallocator

Add an IPAllocator type
Merge pull request #1569 from dchen1107/termination

Initial support to propagating the termination reasons and image failures