add option to display out of date packages like checkupdates

[I-Dream-in-Code]

Can you put in a flag to style it like the checkupdates command?

here's a sample output of checkupdates:

fuse-common 3.2.2-2 -> 3.2.3-1
fuse3 3.2.2-2 -> 3.2.3-1
libgphoto2 2.5.17-1 -> 2.5.18-1
linux 4.16.9-1 -> 4.16.10-1
nvidia 396.24-3 -> 396.24-4

[simon04]

I'm not keen on supporting any imaginable output format – unless it's broadly requested. There's a machine-readable format (RFC 7464), which allows to write converters.