Internal state of the DockerContainer is not reset after container.Terminate(ctx)

[mdelapenya]

Describe the bug
I'm working on exposing the inspectContainer method, and I realised that the Terminate method does not reset the internal state of the DockerContainer instance: raw and uuid

To Reproduce
I'm sending a PR for this. First commit will be a unit test

Expected behavior
After a container is terminated, its internal state (uuid and raw) is reset

docker info
output of the command:

Client:
 Debug Mode: false

Server:
 Containers: 3
  Running: 3
  Paused: 0
  Stopped: 0
 Images: 306
 Server Version: 19.03.1
 Storage Driver: overlay2
  Backing Filesystem: extfs
  Supports d_type: true
  Native Overlay Diff: true
 Logging Driver: json-file
 Cgroup Driver: cgroupfs
 Plugins:
  Volume: local
  Network: bridge host ipvlan macvlan null overlay
  Log: awslogs fluentd gcplogs gelf journald json-file local logentries splunk syslog
 Swarm: inactive
 Runtimes: runc
 Default Runtime: runc
 Init Binary: docker-init
 containerd version: 894b81a4b802e4eb2a91d1ce216b8817763c29fb
 runc version: 425e105d5a03fabd737a126ad93d62a9eeede87f
 init version: fec3683
 Security Options:
  seccomp
   Profile: default
 Kernel Version: 4.9.184-linuxkit
 Operating System: Docker Desktop
 OSType: linux
 Architecture: x86_64
 CPUs: 4
 Total Memory: 7.787GiB
 Name: docker-desktop
 ID: BMI5:JZNA:56SZ:5U24:RYWQ:OJQB:AXJA:LQP6:ZGVF:VGNO:M63Z:6W7X
 Docker Root Dir: /var/lib/docker
 Debug Mode: true
  File Descriptors: 55
  Goroutines: 65
  System Time: 2019-09-05T07:25:03.9382341Z
  EventsListeners: 2
 HTTP Proxy: gateway.docker.internal:3128
 HTTPS Proxy: gateway.docker.internal:3129
 Registry: https://index.docker.io/v1/
 Labels:
 Experimental: false
 Insecure Registries:
  127.0.0.0/8
 Live Restore Enabled: false
 Product License: Community Engine

[mdelapenya]

Merged, thanks!