Align forms and maps

[avocade]

Correctly align maps and forms with columnar layout.

Enable with :align-maps? true and :align-forms? true in .cljfmt.clj config file.

---

Based almost entirely on the great work by reutsharabani in his two PRs:

reutsharabani#1
reutsharabani#3

With a sprinkle of magic dust on top to fix null pointer exceptions and whitespace issues for complex binding forms like map and vector:

(let [{:keys [a b]} (foo)] ...)

and

(let [[a b] (foo)] ...)

[avocade]

Note that it's still a draft PR, and has very little testing yet (except the beefed-up test suite). So play around, but not ready for anything serious yet. Needs more testing in production codebases, and more test cases to cover edge cases.

I'd prefer the blessing of the original author @reutsharabani if this is to be taken forward, since he's done the heavy lifting.

also needs to be rebased on master of course.

[reutsharabani]

Most of the work here was done by weavejester. I expect he is very busy but hopefullyyou can make it happen!

And I am a she not a he :)

[weavejester]

I've had a lull in my work, so this PR came at the right time to encourage me to return to this. I'm currently working on the align-maps branch of this repository, and the work done on all the tests here has been invaluable.

The branch is currently mostly working. I'm currently in the middle of porting all the tests over and fixing any issues they raise. I'll be spending a few days on this so I'm hoping to put this issue finally to rest.

Thanks again to everyone who contributed.