Screensaver for Kobo

Displays a random picture from a directory or a fixed picture or the default "suspended" message.
So far I failed to extract the cover page from the last opened book, but if someone could write a function for that this would be a great enhancement to Koreader!
I have also created a default screensaver picture we could use (but I don't insist on that of course), in that case someone has to create a directory "screensaver" in the koreader main directory, upload the below file (filename: cracked.png, but actually it does not matter as long as it stays a png) and change the defaults.lua entry to
KOBO_SCREEN_SAVER = "screensaver"
Since this is for Kobo only it also could be
KOBO_SCREEN_SAVER = "/mnt/onboard/.kobo/koreader/screensaver"
Unfortunately I can neither create a folder nor upload a binary file in/to the project.
![cracked](https://cloud.githubusercontent.com/assets/7792441/3926490/05a49c68-23f2-11e4-8478-818f440aa15d.png)