Update to bertfrees/clojurec@90870d744c60b591ecaff1281452ea553756dc0e

- Make cljc.core.Closure printable
- New type: cljc.core.Var

    user=> (defn foo [] :bar)
    #'user/foo
    user=> foo
    #<closure@0x107083cc8:0x1079fbe80>
Support switching namespace

    user=> (def foo :foo)
    #'user/foo
    user=> (ns bar (:require [user :as u]))
    nil
    bar=> u/foo
    :foo

- Also hold all exports data in a single vector (instead of one per namespace)
Use pr-str for printing

So that e.g. string are printed properly

    user=> "foo\"bar"
    "foo\"bar"