Added an option to be able to relate issues in different projects.

It can be set in Admin -> Settings (default: false).

git-svn-id: http://redmine.rubyforge.org/svn/trunk@620 e93f8b46-1217-0410-a6f0-8f06a7374b81

app/models/issue_relation.rb

@@ -38,7 +38,7 @@ class IssueRelation < ActiveRecord::Base
   def validate
     if issue_from && issue_to
       errors.add :issue_to_id, :activerecord_error_invalid if issue_from_id == issue_to_id
-      errors.add :issue_to_id, :activerecord_error_not_same_project unless issue_from.project_id == issue_to.project_id
+      errors.add :issue_to_id, :activerecord_error_not_same_project unless issue_from.project_id == issue_to.project_id || Setting.cross_project_issue_relations?
       errors.add_to_base :activerecord_error_circular_dependency if issue_to.all_dependent_issues.include? issue_from
     end
   end

app/views/settings/edit.rhtml

@@ -24,6 +24,9 @@
 <p><label><%= l(:setting_issues_export_limit) %></label>
 <%= text_field_tag 'settings[issues_export_limit]', Setting.issues_export_limit, :size => 6 %></p>
 
+<p><label><%= l(:setting_cross_project_issue_relations) %></label>
+<%= check_box_tag 'settings[cross_project_issue_relations]', 1, Setting.cross_project_issue_relations? %><%= hidden_field_tag 'settings[cross_project_issue_relations]', 0 %></p>
+
 <p><label><%= l(:setting_mail_from) %></label>
 <%= text_field_tag 'settings[mail_from]', Setting.mail_from, :size => 60 %></p>