To help creating/running/… containers using the client for test integration.
This should make test more readable and reduce duplication a bit.
Usage example
```
// Create a default container named foo
id1 := container.Create(t, ctx, client, container.WithName("foo"))
// Run a default container with a custom command
id2 := container.Run(t, ctx, client, container.WithCmd("echo", "hello world"))
```
Signed-off-by: Vincent Demeester <vincent@sbr.pm>
Both names have no real sense, but one allows to make sure these packages
aren't used outside of `integration`.
Signed-off-by: Vincent Demeester <vincent@sbr.pm>