SSH keys: show date added and type instead of excerpt

The public key excerpt column provides limited value for the space it takes up. Two keys, one 4096-bit RSA and one 2048-bit RSA, start with the same 27 characters (or 35 characters, if you include the ssh-rsa).

The default comments in ssh-keygen(1) keys (user@host) aren’t as useful as they could be, and columns for date added (Cloud has this!) and key type would reduce my desire to give each of my keys a custom comment.

A key type column that consists of the first word of each key (like “ssh-rsa” or “ssh-ed25519”) is just as useful as the current excerpt column, but a column that says “RSA (4096 bits)” or “ECDSA (P-256)” or “DSA (1024 bits)” ^ or “Ed25519” (once they are supported) would really tickle my fancy.

^ you could omit the “(1024 bits)” for now, because SSH (as of RFC 4253) is tightly coupled to the FIPS 186-2 version of DSA, where keys must be of that length