cljr-move-to-let

@magnars This isn't finished yet, but I thought I'd add it here in case you were interested in it.  It seems to work when I eval it in Emacs, but the test fails.

Also, I'm sure there are edge cases where it behaves interestingly... for example if the surrounding let is (let [] ...) then you get a blank line above your added let binding.  Also, if there is no surrounding let binding it should probably tell you so, and just fail.