Fix info lookup

[plexus]

When doing a var-info lookup we potentially try three different strategies:
info, lookup, and eval. The second currently always fails, because the "info"
dict is not at the top level in the response message, but nested under an "info"
key.

Compare and contrast:

 (cider-sync-request:info "clojure.core/str")
 (cider-sync-request:lookup "clojure.core/str")
 (cider-fallback-eval:info "clojure.core/str")

Running tests locally I get a failure, but it seems unrelated.

cider-repls when multiple sessions exist always returns the most recently used connection

Traceback (most recent call last):
  buttercup-fail("%s" "Expected `(cider-repls)' to be `equal' to `(#<buffer *b-session:b2:cljs*(8228)> #<buffer *b-session:b1:clj*(7432)>)', but instead it was `(#<buffer *a-session:bb2:cljs*(8909)> #<buffer *a-session:bb1:clj*(4337)>)' which does not match because: (list-elt 0 (different-atoms #<buffer *a-session:bb2:cljs*(8909)> #<buffer *b-session:b2:cljs*(8228)>)).")
  signal(buttercup-failed "Expected `(cider-repls)' to be `equal' to `(#<buffer *b-session:b2:cljs*(8228)> #<buffer *b-session:b1:clj*(7432)>)', but instead it was `(#<buffer *a-session:bb2:cljs*(8909)> #<buffer *a-session:bb1:clj*(4337)>)' which does not match because: (list-elt 0 (different-atoms #<buffer *a-session:bb2:cljs*(8909)> #<buffer *b-session:b2:cljs*(8228)>)).")
FAILED: Expected `(cider-repls)' to be `equal' to `(#<buffer *b-session:b2:cljs*(8228)> #<buffer *b-session:b1:clj*(7432)>)', but instead it was `(#<buffer *a-session:bb2:cljs*(8909)> #<buffer *a-session:bb1:clj*(4337)>)' which does not match because: (list-elt 0 (different-atoms #<buffer *a-session:bb2:cljs*(8909)> #<buffer *b-session:b2:cljs*(8228)>)).

---

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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]

Looks good, but you will need to rebase.

[plexus]

Rebased!

[plexus]

You'll notice I also fixed some more linter warnings that I was getting locally but not on CI. Maybe cause I'm on a more recent Emacs build? (I tend to build from master, last time was end of July).

[bbatsov]

Thanks!