[#125] Fix rotor appender credits

Original PR here: https://github.com/ptaoussanis/timbre/pull/34/files
I'd incorrectly assumed the submitter was the author, but the original
source was actually https://goo.gl/OoBOZU by @postspectacular.

Entirely my error (@ptaoussanis), apologies!

src/taoensso/timbre/appenders/3rd_party/rotor.clj

@@ -1,5 +1,5 @@
 (ns taoensso.timbre.appenders.3rd-party.rotor
-  {:author "Yutaka Matsubara"}
+  {:author "Karsten Schmidt"}
   (:require [clojure.java.io :as io]
             [taoensso.timbre :as timbre])
   (:import  [java.io File FilenameFilter]))