ROADMAP: Remove lifecycle target

I think this is resolved since 7713efc (Add lifecycle for containers,
2015-10-22, opencontainers#231), which was committed on the same day as the ROADMAP
entry (4859f6d, Add initial roadmap, 2015-10-22, opencontainers#230).

Signed-off-by: W. Trevor King <[email protected]>

Author: wking

ROADMAP.md

@@ -10,13 +10,6 @@ Listed topics may defer to the [project wiki](https://github.com/opencontainers/
 
 ## 1.0
 
-### Define Container Lifecycle
-
-Containers have a lifecycle and being able to identify and document the lifecycle of a container is very helpful for implementations of the spec.
-The lifecycle events of a container also help identify areas to implement hooks that are portable across various implementations and platforms.
-
-*Owner:* mrunalp
-
 ### Define Standard Container Actions (Target release: v0.3.0)
 
 Define what type of actions a runtime can perform on a container without imposing hardships on authors of platforms that do not support advanced options.