fix(logger): show error message and backtrace

Author: Issam Hakimi aka Killix

rootfs/opt/fluentd/deis-output/lib/fluent/mixin/deis.rb

@@ -49,7 +49,8 @@ def push(producer, value)
             producer.write(value)
           end
         rescue Exception => e
-          puts "Error:#{map.message}"
+          puts "Error:#{e.message}"
+          puts e.backtrace
         end
       end