Changes to cider-symbol-at-point

[yuhan0]

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Trim leading quotes from symbol, now that clojure-mode treats it as a symbol constituent:
clojure-emacs/clojure-mode#559

This makes it possible to use cider-doc, eldoc, and various other features on symbols with quotes in them like foo'.

Also uses macroexpand to resolve ns-aliased keywords, allowing cider-browse-spec to work on aliased keywords at point.
(Not sure how to write tests for this one)

Would this go under the "changes" or "new features" heading of the changelog?

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[bbatsov]

Would this go under the "changes" or "new features" heading of the changelog?

Let's go with changes.

[bbatsov]

Thanks!