* bin/razor-admin: script to allow users to create DB schema

We don't want users to have to run 'rake db:migrate' since that's a
developer tool. They should migrate their DB with razor-admin
* config.yaml.sample: add an entry for a production environment
* Rakefile(archive): new task to create releasable archive
* lib/razor/initialize.rb: create logdir if it doesn't exist yet
Gemfile: remove gems that were only needed by the CLI

That lives in a separate repo now, so no need to drag these dependencies in
here
ISO unpacking: call into libarchive directly

Instead of shelling out to bsdtar, use the 'archive' FFI wrapper around
libarchive
Ignore the pkg/ subdirectory created by 'rake archive'