Remove unused notification alerts
Refactor blog creation from account

- Creation factory method
- Headers
- Auth token from keychain
Bring back WelcomeViewController

Not renaming for now to avoid losing history
- Headers
- Bring in dependent files and change to work with WPAccount
Collapse external delegate file
Small fixes

- Stack overflow with erroneous find/replace
- Notifications needs auth token in addition to username/password it
  seems.