Use new Docks feature

[Scimonster]

As of Atom 1.17, there's a new Docks feature especially designed for panels like what this package opens. It would simplify usage from a user's point of view, and be more consistent with other Atom packages.

[pghilardi]

@Scimonster ,

You are totally right. The new docks feature is awesome and I will use them in this package. A new version with docks integrated will be released soon.

[dtenenba]

Would this enable the test panel to be resized? I would really like that...right now it takes up a lot of space on my small screen and I can't resize it. If not let me know and I will file a separate issue.