Added a few options to support my digital photo frame project, info display & URG signal

I added a couple options for 'info' formatting, the ability to center it and autofit (reduce font size) when the text would otherwise be cropped.

I also added support for the URG signal to update like --reload except triggered externally

My project is a Raspberry Pi based connected digital photo frame using a surplus LCD monitor, a little more info at: http://scaryprojects.blogspot.com/2013/02/connected-digital-photo-frame.html

BTW, thanks for helping me avoid spending many hours writing my own slide show software in python, would have been fun but I'm too busy and might not have ever finished.

-Mike