Merge pull request #40 from tangosource/developer_rb

Change index to home controller
Category validations&seed
Merge pull request #41 from tangosource/developer_gq

Category validations&seed
Merge pull request #42 from tangosource/developer_rb

Change categories to admin namespace & Delete administrators controller and add home controller to admin
move users to user namespace
Fix bug, a comon user cant access to admin panel without been admin