Fixing typo in copy command

Author: chewbranca

tasks/redis.rake

@@ -93,7 +93,7 @@ namespace :redis do
     end
 
     %w(redis-benchmark redis-cli redis-server).each do |bin|
-      sh "cp /tmp/redis/src//#{bin} #{bin_dir}"
+      sh "cp /tmp/redis/src/#{bin} #{bin_dir}"
     end
 
     puts "Installed redis-benchmark, redis-cli and redis-server to #{bin_dir}"