[feature] Enable pager with environment variable

[erikh]

Hi folks! I love this program.

One thing I'm noticing is that I must supply -p to enable the pager (and piping to less -R doesn't seem to work, and that's a bit surprising, but regardless). I did some sifting around and noticed you had a config file for this stuff, which is cool!

Maybe I'm old school, or simply old, but I'd like to do this with just an environment variable in my shell configuration. I don't foresee myself using the configuration file, and I can't think of many other things I would want to tweak, other than perhaps make the word-wrap a bit more dynamic based on the dimensions of the terminal, which won't work with the environment anyway.

I'm happy to submit this patch if you're willing to accept an environment variable for enabling the pager by default. If you want, I can put in another ticket for the word wrap and do a patch for that, too.