gnupg not where node.js CLI app expects it to be

I installed the prerequisites on Ubuntu 14.04 with 'apt-get install gnupg', although I think it comes preinstalled.

root@hostname:/# keybase version
keybase (keybase.io CLI) v0.8.16
- node.js v0.12.1
- gpg (GnuPG) 1.4.16
- Copyright (C) 2013 Free Software Foundation, Inc.
Identifies as: 'keybase.io node.js client v0.8.16 linux'

root@hostname:/# keybase login
info: Updated file: /root/.cache/keybase/session.json
error: `gpg` exited with code 2
warn: gpg: keyblock resource `/root/.gnupg/secring.gpg': file open error
warn: gpg: keyblock resource`/root/.gnupg/pubring.gpg': file open error
warn: gpg: fatal: /root/.gnupg: directory does not exist!
warn: secmem usage: 0/0 bytes in 0/0 blocks of pool 0/65536

Start by reproducing `keybase login` on Ubuntu after installing GnuPG, then trace the CLI entry point that invokes `gpg` and handles the missing `/root/.gnupg` directory. Done means login no longer fails for this setup, or the CLI reports the required initialization step clearly.

Written by the indexing model from the issue text.