Fixed unsynchronized README.md on cider-connect.

[netpyoung]

or For synchronize, add cider-connect keybinding C-c C-x (C-)c (C-)c to cider.el/cider-start-map

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Thanks!

If you're just starting out to hack on CIDER you might find this section of its
manual extremely useful.

[bbatsov]

Technically the clj and cljs commands are bound in both Clojure and ClojureScript buffers. :-)