https://github.com/clojure/clojure/blob/a26dfc1390c53ca10dba750b8d5e6b93e846c067/src/clj/clojure/java/io.clj#L393
copy actually supports char[] as input (see lines 373-380), so add to docstring.
Prescreened by: Alex Miller - tests already exist for this behavior, just not in docstring