Fix logrotate on Debian
Fix logrotate on Debian

Since we're creating logs as `root:dokku`, the logrotate configuration
needs an `su root dokku` line, just like `su syslog dokku` on ubuntu.

jimjag/dokku,fruitl00p/dokku,fruitl00p/dokku,claytonbrown/dokku,fruitl00p/dokku,claytonbrown/dokku,fruitl00p/dokku,dokku/dokku,elia/dokku,jimjag/dokku,alexquick/dokku,dokku/dokku,fruitl00p/dokku,alexquick/dokku,progrium/dokku,elia/dokku,progrium/dokku,claytonbrown/dokku,alexquick/dokku,elia/dokku,dokku/dokku,jimjag/dokku,alexquick/dokku,dokku/dokku,alexquick/dokku,fruitl00p/dokku,progrium/dokku,jimjag/dokku,progrium/dokku,alexquick/dokku,claytonbrown/dokku,jimjag/dokku,progrium/dokku,dokku/dokku,progrium/dokku,elia/dokku,dokku/dokku,claytonbrown/dokku,claytonbrown/dokku,jimjag/dokku,elia/dokku,fruitl00p/dokku,dokku/dokku,alexquick/dokku,claytonbrown/dokku,jimjag/dokku,fruitl00p/dokku,jimjag/dokku,dokku/dokku,elia/dokku,progrium/dokku,progrium/dokku,elia/dokku,alexquick/dokku,elia/dokku,claytonbrown/dokku