Move all example code under pkg/example

[wfarner]

We were already partially doing this for some plugins, but these ones were split between pkg/plugin and pkg/example. i think it makes everyone's life easier if each plugin's code is centralized.

Signed-off-by: Bill Farner bill@docker.com

[codecov-io]

Current coverage is 67.27% (diff: 0.00%)

Merging #314 into master will decrease coverage by 1.70%

@@             master       #314   diff @@
==========================================
  Files            27         28     +1   
  Lines          1441       1470    +29   
  Methods           0          0          
  Messages          0          0          
  Branches          0          0          
==========================================
- Hits            994        989     -5   
- Misses          355        387    +32   
- Partials         92         94     +2   

Powered by Codecov. Last update 158549a...3b74853

[chungers]

Lgtm

[GordonTheTurtle]

Please sign your commits following these rules:
https://github.com/docker/docker/blob/master/CONTRIBUTING.md#sign-your-work
The easiest way to do this is to amend the last commit:

$ git clone -b "example-code" git@github.com:wfarner/infrakit.git somewhere
$ cd somewhere
$ git rebase -i HEAD~842354164096
editor opens
change each 'pick' to 'edit'
save the file and quit
$ git commit --amend -s --no-edit
$ git rebase --continue # and repeat the amend for each commit
$ git push -f

Amending updates the existing PR. You DO NOT need to open a new one.