Focus and select windows in [i3](https://github.com/i3/i3).

Draws a small label ('a'-'z') on top of each visible container, which
can be selected by pressing the corresponding key on the keyboard
(cancel with ESC). By default, only windows on the current workspace
are labelled.

Focus the selected window:
```shell
./i3-easyfocus
```

It also possible to only print out the con_id of the selected window
and, for example, move it to workspace 3:

```shell
./i3-easyfocus -i | xargs -I {} i3-msg [con_id={}] move workspace 3
```

Or to print the window id and use it with other commands, like xkill:
```shell
./i3-easyfocus -w | xargs xkill -id
```