Code review comment for lp:~townsend/libertine/release-1.2.2

When creating a container, I get the following error:

```
Traceback (most recent call last):
  File "tools/libertine-container-manager", line 492, in <module>
    args.func(args)
  File "tools/libertine-container-manager", line 51, in create
    container_type = self.host_info.select_container_type_by_kernel()
  File "/home/lrp/Projects/2016/libertine-1.2.2/python/libertine/HostInfo.py", line 25, in select_container_type_by_kernel
    if has_lxc_support():
NameError: name 'has_lxc_support' is not defined
```

Probably missing a `self`? See minor diff comments.