Convert promesa.core/all's result to a vector
Convert promesa.core/all's result to a vector

It is often useful to apply functions from clojure.core to
promesa.core/all's result e.g.

(-> (p/all bunch-of-promises)
    (p/then (fn [results]
             (conj results :foo)))
    (p/then something-else))

In the current cljs implementation, results is a javascript native
array. Which means the code above will fail. What I end up doing very
often is calling `vec` or `list` over `results`.

The intention of this PR is to convert the result of a `promesa.core/all` promise
to a clojure datastructure.

While there, I added more documentation.

funcool/promesa,borkdude/promesa