Display keyring info when calling pkg list

[T2JOESl4m2ZpNC]

I tried implementing #184
I noticed you are using a Vec for the keyring_access variable i am assumingfor supporting multiple keys? and needs to be specified on independent lines.
Im not sure about the colors though

the above shodan header looks like this (used it for testing)

-- Description: Find IPs using certificates for target subdomains
-- Version: 0.1.0
-- License: GPL-3.0
-- Stealth: passive
-- Source: subdomains
-- Keyring-Access: shodan
-- Keyring-Access: hibp