Ability to allow non-admin users to create projects (#1007).

This can be enabled in permissions settings. A non-admin user who creates a project is automatically added as a project member (the first role is given, TODO: make this given role configurable).
Projects can be added from the public projects list.

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@2750 e93f8b46-1217-0410-a6f0-8f06a7374b81

test/fixtures/roles.yml

@@ -5,6 +5,7 @@ roles_001:
   builtin: 0
   permissions: |
     --- 
+    - :add_project
     - :edit_project
     - :manage_members
     - :manage_versions