Add the ability to override the oath key name

[awilkins]

Found myself wanting to do this when I set a "friendly" key name when setting up my key at the console.

You can't rename or export TOTP keys once they're in your YubiKey, and my current client has a really annoying workflow for resetting MFA keys, so rather than go through all that and wait another day for my console access to work and be easy, I added an option to the plugin.

Also : small note about getting plugin to work on CLI v2, which has changed how the plugin lookup path works because they went for the "unpack an archive" install route.

Plugin still works fine on v2 at present.

[ws]

@awilkins I appreciate the note about CLI v2, saved me a lot of Googling!