Authentication

Three scenarios:

Scenario 1: No authentication
Scenario 2: Authentication for admin section only, login through admin
Scenario 3: Authentication for admin/frontend sections, login through frontend
Scenario 4: Authentication via token

Libs:
- Has secure password (included in rails)
- ~~Devise~~
- ~~Clearance~~
- Warden
- AuthLogic
- Sourcery

Must support:

- Session cookies
- Database authenticatable
- Reset password
- Account locking
- **Must not conflict with frontend**

Tasks:

- [ ] Investigate authentication libs
- [ ] Support scenario 1
- [ ] Support scenario 2
- [ ] Support scenario 3
- [ ] Support scenario 4?
- [ ] Return 404 if not authenticated?
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