[request] option to start slideshow paused

[aeosynth]

Pretty self-explanatory. I put -D5 in my .fehrc, but sometimes I don't want the slides to change automatically, so when they do, I curse, hit 'h', then 'p'. If I remove the option from my .fehrc, then if I decide I do want automatically changing slides, I have to restart feh.

[derf]

Done.
However, since I don't want to add yet more options to feh for such a simple change, this is also controlled via -D / --slideshow-delay: Specify a positive float to immediately start a slideshow, specify a negative float to set the slideshow-delay, but start in paused mode. Then you can press h to unpause it and have feh automatically change slides.
I hope that's close enough to what you want ;)

There's one bug right now: When starting in paused mode, the first window does not have "[Paused]" in its title. It gets updated correctly once you manually change the image (i.e. by pressing n or →), though. That will be fixed some time later.