Fix process locking and state management

There were races with the way process states.  This displayed in ways,
especially around pausing the container for atomic operations.  Users
would get errors like, cannnot delete container in paused state and
such.

This can be eaisly reproduced with `docker` and the following command:

```bash
> (for i in `seq 1 25`; do id=$(docker create  alpine usleep 50000);docker start $id;docker commit $id;docker wait $id;docker rm $id; done)
```

This two issues that this fixes are:

* locks must be held by the owning process, not the state operations.
* If a container ends up being paused but before the operation
completes, the process exists, make sure we resume the container before
setting the the process as exited.

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>

runtime/proc/proc.go

@@ -40,7 +40,6 @@ func (s Stdio) IsNull() bool {
 
 // Process on a system
 type Process interface {
-	State
 	// ID returns the id for the process
 	ID() string
 	// Pid returns the pid for the process
@@ -57,10 +56,6 @@ type Process interface {
 	Status(context.Context) (string, error)
 	// Wait blocks until the process has exited
 	Wait()
-}
-
-// State of a process
-type State interface {
 	// Resize resizes the process console
 	Resize(ws console.WinSize) error
 	// Start execution of the process