Add Authenticator middleware to the Commander app.

So that the commander server does user authentication (using http
basic auth, kinda)
Fix incorrect invocation of missing function.

An earlier commit renamed all Model#apply_configuration methods to
So we need to change the controllers to call the appropriate method.
Rsyslogd should start after preflight-checks-1

So that it can write out its config file before starting it.
As a result, the preflight-checker does not log to syslog, instead
logging to its own logfile (also under /var/log)
Fix up mismatched function names.

A previous change renamed some functions to #generate_configuration_files.
The controllers need to invoke this new function to trigger the writing out
of config files.
Add the 'adm' group to the system

Becayse rsyslogd needs it. We can eventually get rid of it but we'll
need till we can get commander/preflight-checker to control syslogs
config file (and change it to use another group instead).
Default shell for custom users should be the flightdeck.
Change the way 'debug' and 'upgrade' params are parsed

... and passed to the ImageBuilder and DiskBuilder classes. Send
them in the constructor so that the classes can access it during
the build process to tweak the build in the intended way (such as
instal additional pkgs etc).
Run loadkeys only if the program is installed.
Ensure users homedirs have correct ownership.
Fix naming/spelling errors in Commander::Runner
Fix up test (wrong const name)
Add helper func to determine user ID (for added users)

We'll use the DB id (and some datum) to determine uid's for the users
in the system.
Tweaks to Rakefile

1. Unify all the common apt options (reuse them across invocations)
2. Unify debugging/misc package lists (they were serving similar purposes)