Update README.md to show CIDER and inf-clojure status

[danielcompton]

I noticed that the readme was out of date for CIDER.

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Before submitting a PR mark the checkboxes for the items you've done (if you think a checkbox does not apply, then leave it unchecked):

• [x] The commits are consistent with our contribution guidelines.
• [ ] You've run M-x checkdoc and fixed any warnings in the code you've written.
• [ ] You've updated the changelog (if adding/changing user-visible functionality).
• [x] You've updated the readme (if adding/changing user-visible functionality).

Thanks!

[bbatsov]

Thanks!