Create fake users and roles.

- Add method create_default_users in MockData module
  to create fake users and roles.

- Add rake task create_default_users in app:setup namespace.
  create_default_users calls method create_default_users to
  create fake users and roles.

- Call create_default_users rake task from db:test:prepare rake task.
Refine create_default_users method.

- Refine create_default_users method to stuff fake students.
Fix feature tests.

- Fix feature tests to work with standard set of fake.
Fix feature tests.

- Fix feature tests to work with standard set of fake.

- Fix Feature tests for fake users.
Refine create_default_users method.

- Add roles in a order.

- Change password of user with login 'admin'.
Refine feature tests

- Refine feature tests.
Refine rake db:test:prepare task.

- Include spec_helper.rb file from the task.
Remove semesters from background data

- Remove semesters from background data.
Merge Branches.

- Merge 'origin/test_cleanup_02_18_2013_a' into
  test_cleanup_02_18_2013_a.
Remove redundant code.

- Remove redundant user creation code for feature test.
Restore the removed code

- Restore the removed code.
Fix resource_page_spec.rb test.

- Remove redundant user creation code from the before block.
Refine create_default_users method.

- Refine create_default_users method to add teachers
   with cohort list.
Remove user creation from feature test

- Remove user creation from feature test.
Remove extra fake user

- Remove extra fake user.
Remove school from background data

- Remove school from background data.
Fix feature test

- Fix feature test by changing admin name.
Refine create_fake_data method.

- Update data on rerunning the function.
Refactor create_default_users method.

- Remove redundant code.
Refine create_default_users method.

- Update objects on rerun.