Update Readme

[nerdalert]

Todo: update readme. Need example usage without Compose.

Just running the daemon + the plugin returns docker network create -d ovs my net returns a 404.

Tried the compose and got this:

(='o'=)[root@deb8-150:docker-ovs-plugin$]# docker-compose up -d
Pulling ovs (socketplane/openvswitch:2.3.2)...
2.3.2: Pulling from socketplane/openvswitch
35a6470d0f7d: Pull complete
63536bce8d2b: Pull complete
2bf521d9f3d0: Pull complete
176b6f31a254: Pull complete
2e7d304183d9: Pull complete
90383402eb2b: Pull complete
73185b4131bd: Pull complete
5431aeeebe32: Pull complete
90256da21143: Pull complete
3848a819cf44: Pull complete
e0d5509fe808: Pull complete
c67176847a85: Pull complete
b0d63abd901d: Pull complete
f4b458c14fe0: Pull complete
89aabc43f9ef: Pull complete
21b5a86b035d: Pull complete
36a8f5c4784e: Pull complete
Digest: sha256:4b20d44aaffbdba10dbf3fa51ae31284400aeb0cda1e7bcf9a966a00fde64de8
Status: Downloaded newer image for socketplane/openvswitch:2.3.2
Creating dockerovsplugin_ovs_1...
Pulling plugin (gopher-net/ovs-plugin:latest)...
Pulling repository docker.io/gopher-net/ovs-plugin
Traceback (most recent call last):
  File "<string>", line 3, in <module>
  File "/code/build/docker-compose/out00-PYZ.pyz/compose.cli.main", line 32, in main
  File "/code/build/docker-compose/out00-PYZ.pyz/compose.cli.docopt_command", line 21, in sys_dispatch
  File "/code/build/docker-compose/out00-PYZ.pyz/compose.cli.command", line 34, in dispatch
  File "/code/build/docker-compose/out00-PYZ.pyz/compose.cli.docopt_command", line 24, in dispatch
  File "/code/build/docker-compose/out00-PYZ.pyz/compose.cli.command", line 66, in perform_command
  File "/code/build/docker-compose/out00-PYZ.pyz/compose.cli.main", line 470, in up
  File "/code/build/docker-compose/out00-PYZ.pyz/compose.project", line 230, in up
  File "/code/build/docker-compose/out00-PYZ.pyz/compose.service", line 321, in execute_convergence_plan
  File "/code/build/docker-compose/out00-PYZ.pyz/compose.service", line 209, in create_container
  File "/code/build/docker-compose/out00-PYZ.pyz/compose.service", line 237, in ensure_image_exists
  File "/code/build/docker-compose/out00-PYZ.pyz/compose.service", line 708, in pull
  File "/code/build/docker-compose/out00-PYZ.pyz/compose.progress_stream", line 37, in stream_output
  File "/code/build/docker-compose/out00-PYZ.pyz/compose.progress_stream", line 50, in print_output_event
compose.progress_stream.StreamOutputError: Error: image gopher-net/ovs-plugin:latest not found