show the tag or commit the user is on in the output to aid debugging when a user posts the output somewhere

CLI usage for aliases with multiple recipients

reads from /dev/random need to use count= to actually get that many bytes or else reads might be shorter

Also swith blocksize and count at the owncloud-specific key generation to ensure get as much bytes as you wanted.

Switch blocksize and count when reading from urandom with dd, to prevent getting fewer bytes for the secret key.

Fix typo in dns_update.py.

Replace spaces by tabs in 106-109. See 92c7815d.

Allow users to insert custom nginx configuration directives through new optional files.

if there are no admins when trying to access the control panel, tell the user how to make an admin from SSH

see #140, #155, df20d447

fixes #158

Conflicts:
	setup/start.sh (changes are in questions.sh now)

Conflicts:
	setup/start.sh (change was already applied)

bootstrap.sh: allow overring the tag to checkout by setting the TAG environment variable (helpful for debugging)

broken by b30d7ad8 when the API began to list both real users and archived mailboxes in the JSON response

when deleting my old /usr/local/bin/mailinabox-exchange-autodiscover.php file from existing systems, don't emit an error if the file doesn't exist (added -f)

replace '-t 0' test with an environment variable since '-t 0' is false when standard input has been redirected and doesn't tell us whether or not we can use dialog for input, but Vagrant must be non-interactive

This allows users to add a file /etc/nginx/conf.d/includes/mydomain.com.conf, the contents of which will be included in the server block for mydomain.com.

The secret key that encrypts the backups should not be world readable.

Works like this:

```curl -d "" --user email:password https://.../admin/dns/set/qname/rtype/value```

where the rtype and value default to "A" and the remote IP address of the request, so that a simple, empty POST to

```https://.../admin/dns/set/desktop.mydomain.com```

will point desktop.mydomain.com to the caller's IPv4 address.

closes #140