Update dependencies.

[belucid]

Updates for a couple of out of date dependencies.

[belucid]

Worked fine for me locally but apparently not on Travis. Should (obviously) hold off on merging this until we find out what's up with the updated AWS S3 lib and Jackson

clojure.lang.Compiler$CompilerException: java.lang.NoSuchMethodError: com.fasterxml.jackson.core.JsonFactory.requiresPropertyOrdering()Z, compiling:(aws/sdk/s3.clj:1:1)

[xsc]

@belucid Thanks for providing those - there are actually reasons for not updating, and I might as well document them here.

AWS SDK

I can find some related tickets but nothing that's currently open, but my suspicion is that some pre-compiled parts of Leiningen itself depend on the method mentioned in the Exception which disappears in later versions of Jackson. We could try excluding the Jackson dependencies - but this might cause other problems.

lein-midje

I keep it at 3.1.1 because of marick/lein-midje#47. It might not even affect lein-ancient's tests, I just don't want any future surprises there. :)

We can keep this MR as a reminder, though.

[belucid]

Cool. At least we have it documented now. That's half the battle.