Don't fail if CONTAINER is inexistant.
Drop root privileges if necessary.

This makes it possible to call dokku commands as root.
nginx vhost ipv6 compatibility

IPv6 Compatibility (Nginx Default Site is IPv6 compatible, resulting in not-working vhosts when AAAA DNS entry is set)
Merge pull request #348 from progrium/no-root

Drop root privileges if necessary.
Remove outdated sed. Fixes #346

Starting apps on daemon start has been handed by the upstart 'dokku-redeploy' script for a while. (Also, the format of /etc/init/docker.conf changed and rendered the sed useless.)
Merge pull request #342 from plietar/no-container

Don't fail if CONTAINER is inexistant.
Clean up first. This allows users to get logs from failed runs before they're wiped out. Ref: #354
Link to freenode's webchat
conditional installation of python-software-properties
Remove plugins before copying them again.

This way plugins can rename/delete files w/o having old files lying around.
Only delete core plugins.