Fix #5: Store complete key in leaf nodes.

[nickpalmer]

[kellydunn]

Heya!

Thanks for your PR, I appreciate you taking the time to do it! I have a few comments for you on your work; I think there are some improvements that can be made such that we don't change the method signature of NewArtNode and so that *ArtNode.Key() returns the same type as we originally inserted into the key.

Let me know your thoughts! Would love to have this in the lib :)

-Kelly

[nickpalmer]

Let me know if you have further comments.

[kellydunn]

Thanks again! @nickpalmer :)

I left a few more comments, it looks like there was a temp file that was commited, and I had a small change suggestion to how insertHelper was being invoked.

Aside from that, I think I'd like to see a test that might assert that a newly created LeafNode does in fact have the Key it was intended to have originally. That would be awesome!

(Thanks again for all your hard work!)

[nickpalmer]

I already added a test that asserts the newly inserted key matches the expected key. See art_tree_test.go:230-233