Support name and email from different directories

[prydonius]

e.g.

1. Set karn.yml

/repos/repo:
  name: Adnan A
/repos:
  email: repo@repo.com

1. Run $ karn update in /repos/repo

Expected: both email and name updated to new identity: Adnan A repo@repo.com
Actual: only name is updated, email is unchanged