Allow created containers to be killed and clarify start/delete

Signed-off-by: Mrunal Patel <[email protected]>

Author: mrunalp

runtime.md

@@ -114,24 +114,22 @@ Any changes made to the [`config.json`](config.md) file after this operation wil
 `start <container-id>`
 
 This operation MUST [generate an error](#errors) if it is not provided the container ID.
-Attempting to start a container that does not exist MUST [generate an error](#errors).
-Attempting to start an already started container MUST have no effect on the container and MUST [generate an error](#errors).
+Attempting to `start` a container that is not [`created`](#state) MUST have no effect on the container and MUST [generate an error](#errors).
 This operation MUST run the user-specified program as specified by [`process`](config.md#process).
 This operation MUST generate an error if `process` was not set.
 
 ### <a name="runtimeKill" />Kill
 `kill <container-id> <signal>`
 
 This operation MUST [generate an error](#errors) if it is not provided the container ID.
-Attempting to send a signal to a container that is not running MUST have no effect on the container and MUST [generate an error](#errors).
+Attempting to send a signal to a container that is neither [`created` nor `running`](#state) MUST have no effect on the container and MUST [generate an error](#errors).
 This operation MUST send the specified signal to the process in the container.
 
 ### <a name="runtimeDelete" />Delete
 `delete <container-id>`
 
 This operation MUST [generate an error](#errors) if it is not provided the container ID.
-Attempting to delete a container that does not exist MUST [generate an error](#errors).
-Attempting to delete a container whose process is still running MUST [generate an error](#errors).
+Attempting to `delete` a container that is not [`stopped`](#state) MUST have no effect on the container and MUST [generate an error](#errors).
 Deleting a container MUST delete the resources that were created during the `create` step.
 Note that resources associated with the container, but not created by this container, MUST NOT be deleted.
 Once a container is deleted its ID MAY be used by a subsequent container.