Adds subtasking (#443) including:

* priority, start/due dates, progress, estimate, spent time roll-up to parent issues
* descendant issues tree displayed on the issue view with context menu support
* issue tree display on the gantt chart
* issue tree copy on project copy
* unlimited nesting

Defining subtasks requires the new permission 'Manage subtasks'.
Subtasks can not belong to a different project than the parent task.

Implementation is based on scoped nested sets for fast reads and updates.

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@3573 e93f8b46-1217-0410-a6f0-8f06a7374b81

test/fixtures/enumerations.yml

@@ -19,27 +19,32 @@ enumerations_004:
   id: 4
   type: IssuePriority
   active: true
+  position: 1
 enumerations_005: 
   name: Normal
   id: 5
   type: IssuePriority
   is_default: true
   active: true
+  position: 2
 enumerations_006: 
   name: High
   id: 6
   type: IssuePriority
   active: true
+  position: 3
 enumerations_007: 
   name: Urgent
   id: 7
   type: IssuePriority
   active: true
+  position: 4
 enumerations_008: 
   name: Immediate
   id: 8
   type: IssuePriority
   active: true
+  position: 5
 enumerations_009: 
   name: Design
   id: 9

test/fixtures/issues.yml

@@ -15,6 +15,9 @@ issues_001:
   status_id: 1
   start_date: <%= 1.day.ago.to_date.to_s(:db) %>
   due_date: <%= 10.day.from_now.to_date.to_s(:db) %>
+  root_id: 1
+  lft: 1
+  rgt: 2
 issues_002: 
   created_on: 2006-07-19 21:04:21 +02:00
   project_id: 1
@@ -31,6 +34,9 @@ issues_002:
   status_id: 2
   start_date: <%= 2.day.ago.to_date.to_s(:db) %>
   due_date: 
+  root_id: 2
+  lft: 1
+  rgt: 2
 issues_003: 
   created_on: 2006-07-19 21:07:27 +02:00
   project_id: 1
@@ -47,6 +53,9 @@ issues_003:
   status_id: 1
   start_date: <%= 1.day.from_now.to_date.to_s(:db) %>
   due_date: <%= 40.day.ago.to_date.to_s(:db) %>
+  root_id: 3
+  lft: 1
+  rgt: 2
 issues_004: 
   created_on: <%= 5.days.ago.to_date.to_s(:db) %>
   project_id: 2
@@ -61,6 +70,9 @@ issues_004:
   assigned_to_id: 2
   author_id: 2
   status_id: 1
+  root_id: 4
+  lft: 1
+  rgt: 2
 issues_005: 
   created_on: <%= 5.days.ago.to_date.to_s(:db) %>
   project_id: 3
@@ -75,6 +87,9 @@ issues_005:
   assigned_to_id: 
   author_id: 2
   status_id: 1
+  root_id: 5
+  lft: 1
+  rgt: 2
 issues_006: 
   created_on: <%= 1.minute.ago.to_date.to_s(:db) %>
   project_id: 5
@@ -91,6 +106,9 @@ issues_006:
   status_id: 1
   start_date: <%= Date.today.to_s(:db) %>
   due_date: <%= 1.days.from_now.to_date.to_s(:db) %>
+  root_id: 6
+  lft: 1
+  rgt: 2
 issues_007: 
   created_on: <%= 10.days.ago.to_date.to_s(:db) %>
   project_id: 1
@@ -108,6 +126,9 @@ issues_007:
   start_date: <%= 10.days.ago.to_s(:db) %>
   due_date: <%= Date.today.to_s(:db) %>
   lock_version: 0
+  root_id: 7
+  lft: 1
+  rgt: 2
 issues_008: 
   created_on: <%= 10.days.ago.to_date.to_s(:db) %>
   project_id: 1
@@ -125,6 +146,9 @@ issues_008:
   start_date: 
   due_date: 
   lock_version: 0
+  root_id: 8
+  lft: 1
+  rgt: 2
 issues_009: 
   created_on: <%= 1.minute.ago.to_date.to_s(:db) %>
   project_id: 5
@@ -141,6 +165,9 @@ issues_009:
   status_id: 1
   start_date: <%= Date.today.to_s(:db) %>
   due_date: <%= 1.days.from_now.to_date.to_s(:db) %>
+  root_id: 9
+  lft: 1
+  rgt: 2
 issues_010: 
   created_on: <%= 1.minute.ago.to_date.to_s(:db) %>
   project_id: 5
@@ -157,6 +184,9 @@ issues_010:
   status_id: 1
   start_date: <%= Date.today.to_s(:db) %>
   due_date: <%= 1.days.from_now.to_date.to_s(:db) %>
+  root_id: 10
+  lft: 1
+  rgt: 2
 issues_011: 
   created_on: <%= 3.days.ago.to_date.to_s(:db) %>
   project_id: 1
@@ -173,6 +203,9 @@ issues_011:
   status_id: 5
   start_date: <%= 1.day.ago.to_date.to_s(:db) %>
   due_date:
+  root_id: 11
+  lft: 1
+  rgt: 2
 issues_012: 
   created_on: <%= 3.days.ago.to_date.to_s(:db) %>
   project_id: 1
@@ -189,6 +222,9 @@ issues_012:
   status_id: 5
   start_date: <%= 1.day.ago.to_date.to_s(:db) %>
   due_date:
+  root_id: 12
+  lft: 1
+  rgt: 2
 issues_013:
   created_on: <%= 5.days.ago.to_date.to_s(:db) %>
   project_id: 3
@@ -203,3 +239,6 @@ issues_013:
   assigned_to_id: 
   author_id: 2
   status_id: 1
+  root_id: 13
+  lft: 1
+  rgt: 2

test/fixtures/roles.yml

@@ -14,6 +14,7 @@ roles_001:
     - :add_issues
     - :edit_issues
     - :manage_issue_relations
+    - :manage_subtasks
     - :add_issue_notes
     - :move_issues
     - :delete_issues
@@ -66,6 +67,7 @@ roles_002:
     - :add_issues
     - :edit_issues
     - :manage_issue_relations
+    - :manage_subtasks
     - :add_issue_notes
     - :move_issues
     - :delete_issues