Author: Jérémy Lal <kapouer@melix.org>

---
rake task db:migrate calls db:schema:dump, which writes to
/usr/share/redmine/db, independently of the X_DEBIAN_SITEID instance.
This patch makes it write to (by default)
/var/cache/redmine/${X_DEBIAN_SITEID}/schema.db
so that each instance has its own migration dump.

--- a/config/environment.rb
+++ b/config/environment.rb
@@ -11,6 +11,7 @@
 ENV['RAILS_LOG'] ||= "/var/log/redmine/#{ENV['X_DEBIAN_SITEID']}"
 ENV['RAILS_VAR'] ||= "/var/lib/redmine/#{ENV['X_DEBIAN_SITEID']}"
 ENV['RAILS_CACHE'] ||= "/var/cache/redmine/#{ENV['X_DEBIAN_SITEID']}"
+ENV['SCHEMA'] ||= "#{ENV['RAILS_CACHE']}/schema.db"
 
 # Specifies gem version of Rails to use when vendor/rails is not present
 RAILS_GEM_VERSION = '2.3.5' unless defined? RAILS_GEM_VERSION