- Added gitolite_ops.fdna.com.

- Added update-requirements shell command (to update the requirements
file(s) in a repo, commit and push).

- Don't add SSH keys not configured for that host (I've too many keys theses days which cause too many tries errors).

- Removed debug function, instead debug messages are always sent using
logger directly.

- changed apt-daily alias to use apt-get instead of apt because the apt version that comes with Jessie on my PocketCHIP doesn't support autoclean with apt.