simplify initial database setup deployment rules

config/deploy.rb.SAMPLE

@@ -14,8 +14,6 @@ set :user,                'deploy'              # ssh deploy user
 set :default_stage,       'staging'             # default environment, see config/deploy/
 set :keep_releases,       10
 set :repo_url,            'git://github.com/foodcoops/foodsoft.git'
-set :unique_app_name,     fetch(:application)   # for more complex setups, this can be customised
-                                                # XXX how to get rails environment in here?
 set :deploy_to,            "/www/apps/#{fetch :unique_app_name}"
 
 # more settings which are probably ok

lib/capistrano/tasks/deploy_initial.cap

@@ -22,7 +22,7 @@ namespace :deploy do
       task :config => ['deploy:set_rails_env'] do
         require 'securerandom'
         on roles(:app), in: :groups do
-          db_name = fetch(:unique_app_name).gsub(/[^-_a-z0-9]/i, '')
+          db_name = (fetch(:db_user) or fetch(:application))
           db_passwd = SecureRandom.urlsafe_base64(24).to_s
           db_yaml = {
             fetch(:rails_env).to_s => {