ssh keygen only generates for local user and local host not passed in user and host

[rknechtel]

The current ssh keygen command only generates for local user and local host not the passed in user and host.
It would be good if it would generate a key based on the passed in user and host. I create different users for systems I manage and it would be good if the script would handle generating for any passed in user and host.

Current:
${SSH_KEYGEN} -t $KEYTYPE -b $KEYSIZE -f "${FILENAME}" -N "${PASSPHRASE}"

Proposed addition:
${SSH_KEYGEN} -t $KEYTYPE -b $KEYSIZE -f "${FILENAME}" -N "${PASSPHRASE}" -C "${USER}@${HOST}"

I made the manual change in my local script and it works great! Just might want to add some check to see which way user wants it.