Fix logo showing code.
Enable quizzes category management with administrator user's type.
Disable categories_spec testing code.
Delele user_signed_in condition at the categories controller.
add authenticate_user filtering.
Disable a group of test at rspec.
 Disable a group of test at rspec.
Fix categories spec code.
Delete rspec testing categories view.
Refactoring and modified the definition of categories model
  @Categories.id: model table joining point.
  @Categories.name: HTML input's id
  @Categories.value: HTML input's text or the quizzes topic
  @Categories.description: The long quizzes descrition (255 charector's max)
Fix logo
Merge pull request #148 from harakoji/add_logo

Fix logo
Merge pull request #150 from not001praween001/category-management-permission

Enable quizzes category management with administrator user's type.
Merge pull request #149 from not001praween001/fix-logo

Fix logo showing code.
delete sample notification.
Merge pull request #151 from yuchan/delete-sample-notification

delete sample notification.